MazdaSpeed 2.3L DISI Turbo Blown Engine Resource Thread

[Smoke_31]

I'm not sure of this lift issue you speak of.

I've had her up to 240km/hr (150mph) and it felt planted.

[kwsmithphoto]

I suspect the larger rear spoiler of the MS3 reduces aero life a little bit. But not much.

Basically, it comes down to the "wagon" body style, they're conducive to lift and their isn't an easy way to stop it. I know of a race team who was commissioned by Mazda to make the gen1 MS3 competitive. They tried a number of different wing shapes and locations, but wound up with a large wing in essentially the stock location, but it still didn't work very well...and wasn't legal under the rules.

They decided instead to use the sedan body. Which virtually ever team uses in touring car classes when given a choice. They can put a big wing on the trunk and stay within most race rules that don't allow a rear wing to extend further than the body.

Originally Posted by Smoke_31 I'm not sure of this lift issue you speak of. I've had her up to 240km/hr (150mph) and it felt planted.

In a corner?

[Lex]

So much for the hatch STI ... and even others such as the caddy CTS-V wagon - a serious speed machine.

Originally Posted by kwsmithphoto I suspect the larger rear spoiler of the MS3 reduces aero life a little bit. But not much. Basically, it comes down to the "wagon" body style, they're conducive to lift and their isn't an easy way to stop it. I know of a race team who was commissioned by Mazda to make the gen1 MS3 competitive. They tried a number of different wing shapes and locations, but wound up with a large wing in essentially the stock location, but it still didn't work very well...and wasn't legal under the rules. They decided instead to use the sedan body. Which virtually ever team uses in touring car classes when given a choice. They can put a big wing on the trunk and stay within most race rules that don't allow a rear wing to extend further than the body.

[kwsmithphoto]

Originally Posted by Smoke_31 I'm not sure of this lift issue you speak of. I've had her up to 240km/hr (150mph) and it felt planted.

In a corner?

[kwsmithphoto]

So much for the hatch STI ... and even others such as the caddy CTS-V wagon - a serious speed machine.

The problem with a "wagon" body style is they leave a large, turbulent void behind them, which tends to cause drag and instability/lift. Granted, there are some touring cars that run square back body style, but they generally aren't front runners.

You can mitigate the lift or even create downforce with a really big wing on the roof, but that would cause so much drag that I doubt a stock MS3 would even hit 150. Or 140. They're already drag limited to about 152-153.

[Smoke_31]

Originally Posted by kwsmithphoto In a corner?

Didn't realize you were specifying in a corner. Obviously not doing that speed in or out of a corner with this car.

Sorry if I challenged your internet ego.

[kwsmithphoto]

LOL, you didn't challenge my ego, it was a genuine question.

I've gone about 130 in a 15 degree banked corner (a NASCAR oval) and it wasn't too bad, but I could feel the car getting pretty light in back. I've also hit about 145 at an undisclosed location, straight line, reasonably smooth surface, and while the rear end didn't take to flight it did feel light though. Not too bad though, just got my attention.

Is your car lowered? Mine isn't but it would probably help if it was.

[Smoke_31]

Originally Posted by kwsmithphoto LOL, you didn't challenge my ego, it was a genuine question. I've gone about 130 in a 15 degree banked corner (a NASCAR oval) and it wasn't too bad, but I could feel the car getting pretty light in back. I've also hit about 145 at an undisclosed location, straight line, reasonably smooth surface, and while the rear end didn't take to flight it did feel light though. Not too bad though, just got my attention. Is your car lowered? Mine isn't but it would probably help if it was.

Lol. Sorry, I'm used to dealing with twats on the internet.

I am currently on stock suspension. Soon to be on the Mazdaspeed springs since they have been sitting in my garage for two years. Too busy driving to have them installed I guess

[kwsmithphoto]

No worries, I know how it is.

150mph with the stock suspension is quite fast. You much have great roads up there in Calgary. If I tried that on a Cali highway I'd probably be dead already!

[Smoke_31]

Lol. I'm actually 3 hours north of Calgary but I hear ya.

We have some pretty nasty roads. The speed run was done on the track of course.

[kwsmithphoto]

Geez, 3 hours NORTH of Calgary? How bad does the sledding in Summer need to get before you can drive your car that fast? On a track, of course.

Hey wait, isn't this thread about blown motors?

[FreeFlyFreak]

Originally Posted by kwsmithphoto Hey wait, isn't this thread about blown motors?

FIXED

Originally Posted by kwsmithphoto Hey wait, wasn't this thread about blown motors?

[Smoke_31]

I think I like this thread better when it's not all doom and gloom!

Anyways, back on track.... Who blew up today?

[cld12pk2go]

Originally Posted by Smoke_31 I think I like this thread better when it's not all doom and gloom! Anyways, back on track.... Who blew up today?

Not I. Just 22 PSI of meth fueled fun here:phillyb:...

[wruss64]

Well, I can't really call it a blow up, and looking for suggestions/help here.

2008 MS3 GT 17,150 miles. All the standard mods, AP, DP, FMIC, CC, MSCAI

4 weeks ago I had just installed and aftermarket fuel pump due to fact I had all the other standard mods and wanted to be sure and protect my engine. Well after 3 miles on the test drive I downshifted into 2nd and got a steady misfire, at about 5 MPH. I was monitoring fuel pressure the whole time and everything seemed to be within normal psi ranges. The dreaded "blow up at low rpm engine load " went through my mind, but I have always been careful not to load the engine at low rpm, and was not doing so when this happened.

Turns out I did not blow, but something inside the cylinder and banged up the plug all to heck. No rod through the block or anything as it turns out.

I returned the car to stock and took it to the dealer, after 3 weeks of waiting I was notified yesterday by Mazda that they are denying warranty, that they see no evidence that their parts failed, and something foreign was introduced through the intake system. I don't see how that could be as I had not had the CAI off in months and had driven 500 to 1000 miles. I am going to pay the dealer to pull the head off and see if something broke that caused the issue. That is correct, all Mazda had the dealer do was pull off the valve cover and stop, didn't go any further once they pulled the foreign piece of metal from the cylinder.

So not fully blown up, but I am reaching out for any websites or resources that sell or talk about engine blocks, rebuilds, etc. so I can start getting a plan together to either pull the engine and attempt a rebuild myself, or have the dealer do it.

The car had always driven excellent up to this point, and I had no issues after putting any of the mods on.

Thanks in advance for any help or suggestions.

[Lex]

Were all the parts you installed new?

I am thinking that perhaps something was inside your FMIC or intake piping that needed time to work its way into the manifold and chamber. A really unfortunate event indeed.

[FreeFlyFreak]

Originally Posted by wruss64 Turns out I did not blow, but something inside the cylinder and banged up the plug all to heck. I am going to pay the dealer to pull the head off and see if something broke that caused the issue. That is correct, all Mazda had the dealer do was pull off the valve cover and stop, didn't go any further once they pulled the foreign piece of metal from the cylinder.

Originally Posted by Lex I am thinking that perhaps something was inside your FMIC or intake piping that needed time to work its way into the manifold and chamber. A really unfortunate event indeed.

It sounds like they removed something from a cylinder, what was it?
Did you see what they removed?
Was it identifiable?
Pics of said foreign object?

Seems an awful coincidence that this happened immediately after fuel pump install.
Did you loosen or remove any part of the intake/intercooler system to make the fuel pump install easier? To where something could have dropped in there?

[kwsmithphoto]

My guess is a spark plug tip. If they could pull it out through the spark plug hole, it can't be any bigger!

[kwsmithphoto]

Oh, and FWIW, I've been getting driveabilty stumbles during light loads between 2800 and 3200rpm lately. Smooth idle, no probs at WOT in that range, but there's definitely something going on there during little or no boost.

Stock engine though, and I just drive it like any other car. If the ECU has problems in that transition period, and the motor pops, I'm good as far as warranty. Don't have a Dashhwak or anything so I don't know what's happening, I just feel it driving around town n city traffic. It's not my job as a customer to work around a stumble with a completely stock drivetrain, but I will take it in for it's 30K service and mention it, just to cover my ass. I'm at 13K now so that might take a while.

But I really don't care. The best possible outcome is that it will grenade in the next year or so and Mazda will put a brand new engine in the car so I can feel better about keeping it longer if choose to.

[wruss64]

The piece they pulled out of the cylinder was about the size of a nickel and mangled, unable to tell what it was originally. I just found out Mazda denied warrnaty saying something foreign was introduced into the air intake. BS on that I think. I did take off my cobb intake when I did the fuel pump, but was ever so careful. And I would think it would have taken out my turbo first. The plug was bashed up, but still intact. I just cannot believe Mazda did not at least have the dealer shop take the head off to examine. I have asked how much it would cost me to do this. So far the local dealer is at least acting like the care, we shall see. There is always a chance I dropped something in the intake, but doubtful, especially since it would have been pre-turbo. I let the car idle for 25 minutes as stated when installing the new fuel pump, then was on about the 3rd mile of the 1,000 rpm to 4,000 rpm break in drive, watching my boost gauge to be sure I did not go into boost.

I did actually start the car a few times after it was towed to my house, kept at idle, and only for a few seconds when I was on the phone with the company that sold me the aftermarket fuel pump. They tried to be helpful. When at idle most of the time I heard no noise, a couple of times I heard some clinking around in the engine, but not always. I know I am hoping for a miracle that no damage was done to the cylinder, but I know it is doubtful.

[FreeFlyFreak]

The size of a nickle, that is pretty big, I doubt something that big would have made it through the turbo with out destroying it, and I cant even imaging it making it through the intercooler.

You sure its not the head off a valve, sounds about the right size.....
Isnt that what mazdaspeedgirl or (whatever she is called) have happen....... twice??
Head came off number two cylinder valve.

[wruss64]

Well I believe it is cylinder #2, 2nd in from drivers side? Might not have been quite the size of a nickel, part isn't around the car any more, probably sent off to Mazda, but it was at least the size of a dime or more.

I just don't see how I could have dropped anything in when I worked on the fuel pump. And I had 500 miles on the car since the last mod, which was a FMIC, but I blew air threw all the tubes etc before installing. I am hoping the Dealer won't want an arm and a leg to take off the head so I can know for sure, and have piece of mind it was not a problem caused by the engine and move on to what I will do next. Which will be either rebuild, replace, or trade for a CX7. I already primed the new car guys yesterday by test driving one. If the numbers worked out on what they would give me for my car, I might consider it. But I would sure miss driving the MS3.

[802MS3]

I think you have enough evidence if the turbo isn't damaged. no way a piece of metal could go through the compressor without mangling that too. just sounds like another lame attempt by Mazda to get out of a warranty claim.

[Byron]

I know exactly when the con rod in my engine got bent; it was at 10 psi of boost in 3rd gear at 2800-2900 rpm after a 20 minute drive at 40 mph in 4th gear on my way home. It knocked like crazy and I got out of the throttle right away. The engine was making a tapping noise right after this happened. I limped it home (this was a Friday night) I took it to work and removed a couple of mods (test pipe, PTP HPFP, PTP balance shaft delete kit and oil pan baffle) I could not see any damage to the con rods at that time.

I took it to the dealer and they decided it was a "Top End" noise and pulled the head off, did a full valve job, replaced the timing chain and tensioner (this took almost a month in the shop) When they called and said it was ready I went down and picked it up but it was making the same noise (maybe at slightly less volume but the same noise). I called them Monday morning and told them it was not "fixed" and they told me the factory rep told them that Mazda was all done and were not going to do anything else for me. Keep in mind I had owned the car for 3 years 3 months and 39,950 miles. I was holding their feet to the fire on the Driveline warranty. I was driving the car back and forth to work but not doing anything crazy with it.

I finally got tired of talking to the service writer and the lead mechanic and asked to see the Service Manager. I spent an hour in the SM's office with the Service writer. I took a lot of information that I had found online (this site and others) about some of the problems that have been going on with the DISI engines. I had pulled the valve cover off and checked the valve clearance and then did a leak down test, #3 cylinder had over 55% leak past the rings!! The other 3 cylinders were all below 8%. I asked if they had done a leak down and they said they had, I asked them to look in the records and see what the test numbers were. GUESS WHAT, they had the same numbers BEFORE they pulled the head off and did the valve job, they did not check it again after they did the work.

The SM told me that the District Service Rep from Mazda was going to be there the next day and if I would bring the car back he would discuss it with him and show that the noise was still there. I told him I would be back and thanked him for is time. As I was getting into my car the SM and the Sw were walking down the sidewalk right in front of my car when I started it, the noise was there and they both heard it, the SM asked me to open the hood and he listened very carefully and said "We Are Not Done With This Yet".

On the way back to my shop (less than 2 miles from the dealership) I was pulling away from a stop light with a cop car in the lane next to me and at 25 mph at about 3 psi of boost in 3rd gear it kicked the #3 con rod out of the engine. I had the car delivered back to the dealership (less than 40 minutes after I had left the SM office). The next day they called and said they had "ordered" a new engine and I should come and get a loaner car.

This car had done the "big knock" twice before both times after more than 20 miles at freeway speeds at a steady cruise and it happened either at the end of the off ramp as I pulled away or at the very next stop. I am sure the crankcase breather system was causing oil to puddle in the intake manifold. When they had the head off the first time it was in for work there was oil in the intake manifold and signs of some oil in the combustion chamber. I have done 3 open track driver's schools with this car (I'm an instructor) and put between 125-150 miles each day with no problems at all so it is interesting that the problem happened after driving the car at 40 mph for 20-25 minutes at low engine speeds and less than 10 psi of boost. I have oil pressure, oil temp, water temp, boost pressure (with a tattle tale) and Intake air temp measured at the throttle body gauges that have been on the car for about 34,000 miles so I have been keeping track of the engine for most of its life.

I now have an oil catch can on the line between the intake manifold and crankcase with an extra check valve between the manifold and OCC. I also have Oil catch can on the line from the VC to the intake pipe with a one way check valve on the line. When the engine is on boost the valve between the Intake Manifold and the OCC closes and if there is any crankcase pressure it is allowed out through the valve cover and through the check valve into the occ. When there is vacuum in the intake manifold it tries to pull a vacuum in the crankcase because the valve at the VC is closed so no air can get pulled through the engine and into the Intake manifold, the only air available is just blow by. In 3000 miles I have taken less than 3 tablespoons of liquid out of the Intake manifold catch can and none out of the one on the valve cover. I used a bore scope to look into my intake manifold after a 60 mile cruise on the freeway and found no sign of oil or moisture at all. I'm still keeping track of it but I have hope.

I don't think this engine has "WEAK RODS" at all, I put almost 300 miles on a connecting rod that was so badly bent the rings were not seating any more, one that was making so much noise that the service manager was shocked to hear it at idle. My engine "Hydro locked" it's self on its own oil. BTW I don't LUG the engine but I have never been shy about getting on the gas in all the gears 1-5 in the 2500 rpm range; it pulls like a freight train. This was a specific event that caused the damage and as far as I am concerned it had nothing to do with "WEAK" parts or lugging, it was a bad design of the crankcase breathing system and intake manifold design that allowed the oil to puddle and then at the first time I tried to accelerate and opened the throttle enough to move a lot of air that puddle got "sucked" into one cylinder in a quantity big enough to cause HYDROLOCK.

Just so you know I restore Vintage Racing cars for a living. I have been building race engines for road racing for the last 20+ years. I have done BMW, Porsche, Ford, Chevrolet, Ferrari, Alfa, VW, Cosworth, BRM, and Coventry Climax engines and have seen my fair share of engines blown up. This is my street car, my daily transportation not my race car, I'm not looking for 600 hp I enjoy the 256 HP I'm getting right now (I have my own dyno). I have driven over 175 different race cars over the years, everything from a 1926 Stutz to mid 80's ground effect F1 cars, 700 hp Can Am cars to 120 hp 900 lb Lola sports racers, that is me in a 917K Porsche in the pictures. 250 hp in a 3200 lb station wagon is a lot of fun but I am not trying to kid myself into thinking it is anything other than a fun street car.

Sorry about the long rant just needed to finally get this off my chest.

[boosties]

Boosties
Car; 2007 MazdaSpeed 3 91,000 MILES
Cylinder; unknown
Damage; unknown
RPM; see speed
Mods; Cobb SRI, Corksport TP
Exhaust Manifold; Stock
Situation; 30 MPH, going up a hill i'm guessing it's about a 50 degree incline
Other: Same situation as member s-retire.
"There was no indication of low oil condition prior to engine failure. The low oil pressure indicator light did not illuminate until after the motor quit. There was no increase in operating temp."
Warranty; no warranty, car is over 60,000 miles

[wruss64]

Well more on my saga of the piece of material that bounced around in the cylinder, and just to recap, 2008 MS3 GT 27,135 miles so should be under warranty. Since Mazda denied warranty saying something was introduced into the intake, I asked the Service manager to quote me labor to just pull the head. $600 is what he told me today, more than I had thought it would be. So the dilemma is do I just throw $600 out there hoping that a valve is broke and maybe I can go back at Mazda for warranty, or tow it home and try it myself. I am mechanically inclined, but last engine I rebuilt was on a 1966 Corvette 327 engine LOL. I have a 2nd vehicle good ole reliable 98 Jimmy to drive so the MS3 could be in the garage as a summer project. But I just don't know how involved this would be, past the obvious. Also, if I was to tow it home, take the head off myself, find a broke valve, do you think not having the work and discovery done by an authorized Mazda dealer with give Mazda North American ammunition to deny warranty again?

The Service Manager did say the $600 would of course apply towards labor if I got lucky enough to just need work done on the head, if the cylinder is not scored. But no way to know what I am looking at as far as repairs until that head comes off.

I am going to try and get a picture of the piece of material that was pulled from the cylinder and post it. Cannot really tell what it was originally. But I did see a pic on another site of the under side of the head, saw the color of the valves, and the piece of material did look dark like two of the valves in pic I saw. Probably wishful thinking at this point.

Anyway, I appreciate the listening and the input.

[Lex]

Byron, hope you got my PM and can answer. I appreciate your insight. The scenario you described is quite common - high KR after highway cruise ... but I am not convinced it it hydrolock for several reasons:
- I used to be able to induce this knock/KR spike with a boost spike after hwy run at will.
- The "resonance" picked up by the knock sensor is not the same for a detonation event and hydrolock so you shouldn't see KR on the dash hawk in the case of hydrolock unless the event damaged the rotating assembly.
- I had an oil CC with a secondary PCV for a year and could induce this condition. I only alleviated this problem when I reduced dynamic compression ratio and boost spikes.
- The PCV system is designed in such a way that "large" amount of oil are very difficult to find themselves in the intake manifold at once. Oil vapor sure.
- If this condition is present on the hwy, I presume the same condition would be present when cruising at say 30mph in the city. Or even under high vacuum at idle for example.
- If oil was hydrolocking the engine that accumulated under vacuum conditions, we would see a lot of Duratec motors blow like this as they have the same PCV system setup. Duratecs have been sold for the last decade in many vehicles.

Looking forward to your thoughts.

Originally Posted by Byron I know exactly when the con rod in my engine got bent; it was at 10 psi of boost in 3rd gear at 2800-2900 rpm after a 20 minute drive at 40 mph in 4th gear on my way home. It knocked like crazy and I got out of the throttle right away. The engine was making a tapping noise right after this happened. I limped it home (this was a Friday night) I took it to work and removed a couple of mods (test pipe, PTP HPFP, PTP balance shaft delete kit and oil pan baffle) I could not see any damage to the con rods at that time. I took it to the dealer and they decided it was a "Top End" noise and pulled the head off, did a full valve job, replaced the timing chain and tensioner (this took almost a month in the shop) When they called and said it was ready I went down and picked it up but it was making the same noise (maybe at slightly less volume but the same noise). I called them Monday morning and told them it was not "fixed" and they told me the factory rep told them that Mazda was all done and were not going to do anything else for me. Keep in mind I had owned the car for 3 years 3 months and 39,950 miles. I was holding their feet to the fire on the Driveline warranty. I was driving the car back and forth to work but not doing anything crazy with it. I finally got tired of talking to the service writer and the lead mechanic and asked to see the Service Manager. I spent an hour in the SM's office with the Service writer. I took a lot of information that I had found online (this site and others) about some of the problems that have been going on with the DISI engines. I had pulled the valve cover off and checked the valve clearance and then did a leak down test, #3 cylinder had over 55% leak past the rings!! The other 3 cylinders were all below 8%. I asked if they had done a leak down and they said they had, I asked them to look in the records and see what the test numbers were. GUESS WHAT, they had the same numbers BEFORE they pulled the head off and did the valve job, they did not check it again after they did the work. The SM told me that the District Service Rep from Mazda was going to be there the next day and if I would bring the car back he would discuss it with him and show that the noise was still there. I told him I would be back and thanked him for is time. As I was getting into my car the SM and the Sw were walking down the sidewalk right in front of my car when I started it, the noise was there and they both heard it, the SM asked me to open the hood and he listened very carefully and said "We Are Not Done With This Yet". On the way back to my shop (less than 2 miles from the dealership) I was pulling away from a stop light with a cop car in the lane next to me and at 25 mph at about 3 psi of boost in 3rd gear it kicked the #3 con rod out of the engine. I had the car delivered back to the dealership (less than 40 minutes after I had left the SM office). The next day they called and said they had "ordered" a new engine and I should come and get a loaner car. This car had done the "big knock" twice before both times after more than 20 miles at freeway speeds at a steady cruise and it happened either at the end of the off ramp as I pulled away or at the very next stop. I am sure the crankcase breather system was causing oil to puddle in the intake manifold. When they had the head off the first time it was in for work there was oil in the intake manifold and signs of some oil in the combustion chamber. I have done 3 open track driver's schools with this car (I'm an instructor) and put between 125-150 miles each day with no problems at all so it is interesting that the problem happened after driving the car at 40 mph for 20-25 minutes at low engine speeds and less than 10 psi of boost. I have oil pressure, oil temp, water temp, boost pressure (with a tattle tale) and Intake air temp measured at the throttle body gauges that have been on the car for about 34,000 miles so I have been keeping track of the engine for most of its life. I now have an oil catch can on the line between the intake manifold and crankcase with an extra check valve between the manifold and OCC. I also have Oil catch can on the line from the VC to the intake pipe with a one way check valve on the line. When the engine is on boost the valve between the Intake Manifold and the OCC closes and if there is any crankcase pressure it is allowed out through the valve cover and through the check valve into the occ. When there is vacuum in the intake manifold it tries to pull a vacuum in the crankcase because the valve at the VC is closed so no air can get pulled through the engine and into the Intake manifold, the only air available is just blow by. In 3000 miles I have taken less than 3 tablespoons of liquid out of the Intake manifold catch can and none out of the one on the valve cover. I used a bore scope to look into my intake manifold after a 60 mile cruise on the freeway and found no sign of oil or moisture at all. I'm still keeping track of it but I have hope. I don't think this engine has "WEAK RODS" at all, I put almost 300 miles on a connecting rod that was so badly bent the rings were not seating any more, one that was making so much noise that the service manager was shocked to hear it at idle. My engine "Hydro locked" it's self on its own oil. BTW I don't LUG the engine but I have never been shy about getting on the gas in all the gears 1-5 in the 2500 rpm range; it pulls like a freight train. This was a specific event that caused the damage and as far as I am concerned it had nothing to do with "WEAK" parts or lugging, it was a bad design of the crankcase breathing system and intake manifold design that allowed the oil to puddle and then at the first time I tried to accelerate and opened the throttle enough to move a lot of air that puddle got "sucked" into one cylinder in a quantity big enough to cause HYDROLOCK. Just so you know I restore Vintage Racing cars for a living. I have been building race engines for road racing for the last 20+ years. I have done BMW, Porsche, Ford, Chevrolet, Ferrari, Alfa, VW, Cosworth, BRM, and Coventry Climax engines and have seen my fair share of engines blown up. This is my street car, my daily transportation not my race car, I'm not looking for 600 hp I enjoy the 256 HP I'm getting right now (I have my own dyno). I have driven over 175 different race cars over the years, everything from a 1926 Stutz to mid 80's ground effect F1 cars, 700 hp Can Am cars to 120 hp 900 lb Lola sports racers, that is me in a 917K Porsche in the pictures. 250 hp in a 3200 lb station wagon is a lot of fun but I am not trying to kid myself into thinking it is anything other than a fun street car. Sorry about the long rant just needed to finally get this off my chest.

[Byron]

There is also the design of the intake manifold, the throttle body and majority of the manifold it's self are below the intake ports in the head, it may be that this intake manifold design is prone to allowing the oil vapor to condense and puddle in one spot. It would then take a sudden flow of air or cornering to move it so it would go down one runner into a single cylinder in one intake cycle to do the hydrolock damage. If the amount of oil is not large enough to fill the chamber and cause the hydrolock condition it would sure cause a knock, smoke , running issue like many have had ( including me on other occations) but it just takes that one time to do the damage.

[Lex]

I am certainly inclined to think prolonged highway cruise is an operating condition that lends itself to knocking and that many of our motors go out in similar ways to what Byron experienced. Here's something interesting - we are not alone. The Cobalt DI LNF motors suffer from a similar issue.

A GM engineer describes what he believes highway knock has at the source. This is similar to my findings/feelings and both our motors and the LNF operate in similar ways. I have highlighted point of interest in red.

I hope this clears up some confusion on knock and how many of the motors go to heaven. Remember that our engine is 9.5:1 static CR compared to the LNF 9.2:1 making it more knock happy. Also, they have a smaller motor meaning less ability to spool the turbo and boost spike and shorter stroke meaning they are less prone to bending rods.

http://www.solsticeforum.com/forum/f...visited-61506/

Oh this is fun. If this thread is intended to define a cause for "detonation" then I think you first need a few definitions and some clarifications to guide the ensuing hypothesis. First. Lets define two kinds of detonation or knock. - Knock - will, can, or should be defined as spontaneous combustion of a fuel air mixture caused by a rapid rise in cylinder pressure from a spark ignition event resulting in the auto-ignition of said fuel air mixture ahead of the flame front from said spark event. This is the most typical kind of knock, typically a result of too much spark. - Pre-ignition - should be defined as the ignition of the cylinder charge prior to the spark event, caused by a variety of not so well understood factors. Second, we should clarify some operating condition myths. - The ECU does not adjust desired lambda leaner than 1.0 during a highway driving cycle, except for closed loop toggling. We would saturate the catalyst with oxygen and violate the Nox limit for an emissions test if we did. - Most "lean spikes" in the exhaust under heavy load are caused by scavenging (high overlap allowing boost pressure to push fresh air in to the exhaust stream), this fresh air pushes the pre-cat O2 sensor lean, however in cylinder air charge actually ends up rich because the ecu fuels for the measured amount of air, even though it is not all trapped in the cylinder. - The GM performance tune will probably not be any worse for pre-ignition than the standard production calibration because pre-ignition has very little to do with spark advance. Pre-ignition is not detectable by knock sensors because the ignition event occurs ahead of the spark event, and does not produce the same frequency oscillation as typical knock event. In short, there is not a whole lot the ECU can do to stop pre-ignition except cutting off the fuel. Ok, anyway, on to the meat. It is well known that knock events in combustion engines are closely tied to fuel quality and pressure rise within the cylinder. That being said, high effective or geometric compression ratios (IE, BOOST) will increase an engines sensitivity to knock, as well as aggressive spark advance. Furthermore the farther you retard spark advance, the more heat you introduce in to the combustion chamber and surrounding components. This means that as you retard spark, you may delay the burn such that it reduces the likely hood of knock, however you will begin to heat up the system causing the sensitivity of knock to increase. One could say that sustaining these high load / retarded spark conditions will just produce a never ending spiral of knock / spark retard / more knock / more spark retard. The ecu is designed in such a way that at a certain point of spark efficiency loss it stops adding boost and you just begin to lose torque. This allows the engine to protect itself against damage from these kinds of events. - Weather plays a huge role in the capability of the engine controller to deliver a desired torque. The more torque you demand from the LNF, the more sensitive it will be. For instance, dry air knocks a lot more than humid air, hot air knocks more than cold air, cold air is dry, etc etc etc etc. - All boosted engines will knock! The fact is that you are continuing to cram more air in to a cylinder than it's naturally aspirated limit, it's going to knock. The question of course is how much and for how long. The ECU's knock control system, if operating properly, manages the spark such that it does not continually knock during a driving cycle. -- There are a few adapts for this system, one even for fuel. Basically if the ECU is convinced that you have put crap in your gas tank it permanently reduces spark to adjust for that driving cycle. The next driving cycle it tries again. --- The more likely cause for knock after a long highway trip are two fold: - - - - First: Everything is warm. The combustion chamber and piston, etc, have all gotten hot from driving for such a long time at moderate load. - - - - Second: The ECU has probably not been operating in a "high" knock intensity area, so more than likely you will not have any spark knock correction. --- Addressing knock on tip in after a hard accel. This goes to the boost and retarded spark comment. You will knock on tip in after a hard acceleration, you just got everything hot with boost and retarded spark! If you see the knock retard light up after this kind of an event, say you ran up a hill at WOT, and now are driving straight and level and it's knocking, don't be concerned. The knock system is doing it's job! if you don't see the knock system doing anything, then be worried. While audible knock is concerning, a quick couple of events isn't going to kill anything. it's the sustained knock thats a problem. Of course, if you are concerned about it, try a higher grade gasoline, if available. If you are concerned about the mechanics, pull the plugs and look for corrosion of the side wire, it'll look like cavitation, also borescope the engine and look for nibbling around the edges of the piston, a little is no big deal, if it looks like a bread carving knife you have a problem. A quick couple of notes about pre-ignition. There are a few things that can cause this, one of which is spark retard. Basically you get the plug so hot it turns in to a torch and ignites the fuel as it is sprayed in to the cylinder. You'll know when this happened because everything will seem fine and then the engine will be laying on the floor disassembled in front of you. - The other kind is caused by a mixing of constituents in the combustion chamber, oil, fuel, air, crap, etc. That causes ignition during the compression stroke and results in a huge knock event. Tuners have typically run rich air fuel mixtures to get around this, however with both the stock and GMPP tunes it shouldn't be required. Personally I have only had one or two "ping" events in my solstice in the 33k miles that i have on it, however I watch the knock sensors pretty frequently and they are indeed working. Ok in summary. Knock is generally cause by too much spark, lean AFR, or bad gas. Pre-ignition is generally caused by an overheated spark plug or constituent mixing that allows for combustion before the spark event. In the hopes of providing actual data for a discussion I would like to entertain some more specific information about the types of events you are seeing Jazz. - I understand highway, so I'm guessing warm engine, say 95-100C coolant, what kinds of days, hot? cold? muggy? all of the above? Do you have a data trace? I can compare with some data from my car. I hope that I have provided some insight and not just blabbed __________________ I am a GM Engineer, My views / opinions on this forum do not express any views of GM, they are my own and mine alone. I work for GM Powertrain, I own a solstice.

[Lex]

Moar from wikipedia:

Engines using indirect injection generally have lower levels of knock than direct injection engine, due to the greater dispersal of oxygen in the combustion chamber and lower injection pressures providing a more complete mixing of fuel and air.

And yet moar ... this is gold boys and girls ... http://www.eurojournals.com/ejsr_34_4_06.pdf

Another important challenge for DI is the extremely short time for hydrogen–air mixing. For early injection (i.e., coincident with inlet valve closure (IVC)) maximum available mixing times range from approximately 20–4 ms across the speed range 1000–5000 rpm, respectively [3]. This insufficient time leads to unstable engine operation at low hydrogen-air equivalence ratios due to insufficient mixing between hydrogen and air [9]. Late injection, as a solution, was investigated by Mohammadi et al. [4]. However, this measure is insufficient and the system will be susceptible for pre-ignition as stated above. Therefore, additional transactions like utilization of other techniques such as EGR and after-treatment methods are required to bring the NOx emission to acceptable level [4]. The present contribution introduces a model for a four cylinders, direct injection H2ICE. GT-Power software code is used to build this model. The objective of this study is to investigate the effect of air fuel ratio on the engine performance of the direct inject engine.

[wruss64]

Well do I ever have egg on my face. Not Mazda's fault at all. Not sure how I dropped something in the BOV intake but I did. Very small washer or something, See pics. Not sure how it kept out of the engine for the 100 miles it did. Thing is, engine looks almost like I could put a plug back in and drive it. Obvious pitting on the piston head. The valves look good, #3 cylinder was the cullprint, head is pretty pitted up. Mechanic said the valves moved freely with the cam.

The cylinder walls did not look or feel scored. You can see a vertical line, but cannot feel it with fingernail or finger. Mechanic didn't really say, "oh yeah" that cylinder is screwed, but did worry about small material between cylinder walls and rings. He did also say compression was at 90, other 3 where at 160 or so. I am going to buy a new or rebuilt engine, but I just think that pulliing the rod and piston and replacing the piston and rings, it might run. The mechanic said the pitting on the head could cause problem with combustion due to the way the fuel is "atomized" at high pressure. Anyway, take a look, thanks for the comments. Lesson learned, double double double check everything.

[FreeFlyFreak]

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Doh!

[RicanSpeed6]

Anyone know of someone or a place thats selling a 2.3l disi turbo motor...mine just blew after 82k miles... -.-

[Lex]

Originally Posted by RicanSpeed6 Anyone know of someone or a place thats selling a 2.3l disi turbo motor...mine just blew after 82k miles... -.-

Details on how it blew?

[boosties]

mine just blew after 91k miles, can someone tell me why there was oil in my intake tubing as well as around my filter?

[Lex]

Originally Posted by boosties mine just blew after 91k miles, can someone tell me why there was oil in my intake tubing as well as around my filter?

My guess is that it was coming from the valvecover vent because you were getting lots of blowby because you perhaps had a bent rod or poor compression. Did you make a hole in the block or just run out of oil?

[wruss64]

I have seen a few used engines out there, 1 on Ebay motors for $2,995 or offer and $450shipping, others for around $3,200 to $3,400 with or without shipping. You can also use the CX7 engine. I am going with a new engine from the Dealer for the warranty. They quoted $3,950 for the engine. Plus I think I can get them to knock about $1,000 or so off of the $2,500 labor they quoted to drop the old engine and put the new one in. I don't think they would negotiate on labor if I source my own engine. Rebuilts sometimes are costing more than new.

I am wondering what I will be able to sell my old engine for. No low end damage, just some ever so slight scoring on the one cylinder, and head will probably need to be reworked. I could put a spark plug in it today and it would run, just lower compression on one cylinder. How long it would run for might be another question LOL.

I have a couple of emails from places that have given me a quote if you want to pm me I can forward their info to you.

[boosties]

Originally Posted by Lex My guess is that it was coming from the valvecover vent because you were getting lots of blowby because you perhaps had a bent rod or poor compression. Did you make a hole in the block or just run out of oil?

The dealership said it just ran out of oil

[fridgelips]

I just blew my friggin motor. 19,000 miles.. not on the gas, just coasting in 4th coming up to a red light.....BOOM! im reading all these posts and getting scared.... Has ANYBODY had luck with the waranty? If so what kind of shit can i expect and look out for. Any help would be great. Thanks

[holeinmypocket]

Originally Posted by fridgelips I just blew my friggin motor. 19,000 miles.. not on the gas, just coasting in 4th coming up to a red light.....BOOM! im reading all these posts and getting scared.... Has ANYBODY had luck with the waranty? If so what kind of shit can i expect and look out for. Any help would be great. Thanks

that sucksssssssssssssssssssssssssssssssss....welcome to the blown up club