MazdaSpeed 2.3L DISI Turbo Blown Engine Resource Thread

[cld12pk2go]

Just tossing this out there...

I monitor knock 100% of the time I am in the car and over ~1.0 load.

I have noticed that I often have 1-2° of knock before my engine is fully warmed up when under moderate to high loads. This usually extends until as long as ~5 minutes after my engine coolant is at temp.

After ~10 min from startup, I can usually go to the same loads with essentially 0 knock.

This has resulted in my tending to not get on my car until after a through warming period.

I do not know if this directly relates to anyone's troubles, but I figured I could be a factor if some people are not watching the KR as closely.

[FreeFlyFreak]

Originally Posted by cld12pk2go I have noticed that I often have 1-2° of knock before my engine is fully warmed up when under moderate to high loads. This usually extends until as long as ~5 minutes after my engine coolant is at temp. After ~10 min from startup, I can usually go to the same loads with essentially 0 knock.

I have exactly the same experience.
Coolant temp related knock..... but I get more sometimes up to 6

[cld12pk2go]

Originally Posted by FreeFlyFreak I have exactly the same experience. Coolant temp related knock..... but I get more sometimes up to 6

I sometimes get more, but practically never over 4° and only seldomly over 2°.

[SpoolinWagon08]

Originally Posted by FreeFlyFreak I have exactly the same experience. Coolant temp related knock..... but I get more sometimes up to 6

I had the opposite effect.. 0.0 knock cold, only getting worse the longer I had the car running. Although I never WOT the car before it's warmed up so I don't have the logs to support this theory.

[SpoolinWagon08]

Originally Posted by 6SpeedTA95 What'd the dealer say when you dropped it off?

I haven't taken it to the dealer yet.. Although I took all the mods off, hoping it will blow soon, then I can have it towed directly there.

I did a pretty good job about leaving no signs of modifications. Very happy I never added exhaust mods.

Here's hoping I go boom this week!

[6SpeedTA95]

Originally Posted by SpoolinWagon08 I haven't taken it to the dealer yet.. Although I took all the mods off, hoping it will blow soon, then I can have it towed directly there. I did a pretty good job about leaving no signs of modifications. Very happy I never added exhaust mods. Here's hoping I go boom this week!

If you have a vibration why would you wait till it pops????? why wouldn't you take it in? if they say there's no problem and then you blow then its really on the dealer....

[kwsmithphoto]

Good point. Let them either say there isn't a problem, or test it and find a more easily fixed problem than a hole in the block.

[DaleNixon]

I know a guy in college station with an MS6 that blew up during an autocross event yesterday. I'll try to get more details.

[scratchbuilt]

Hello all,
I thought I'd toss my situation into the list of damaged rods.
2007 CX7 bought in August 2006, early production. No mods other than Forge BOV. Ok, here's a number for ya, 180,000 miles and the oil is changed by the dealership only and always between 3 and 7k.
Situation: Driving to work in the morning @ approx 65mph and accelerating to pass a slower vehicle when the engine started ticking loudly. It never sounded any better or worse during the remainder of my drive to work. (35miles)

The oil level did not register on the dipstick when checked upon arrival. I had about 4k on this oil change. Where did the oil go?????? I added new oil to top off and the ticking remained. Even after adding about 4 quarts, the remaining oil was so black it made the new oil as black as night as well.
Damage: #3 connecting rod bent and damaged piston when it bottomed out against the crank.
All pistons have hard crusty deposits around the rings and skirts. Bad oil or over heated pistons?
As I said before, the oil gets changed by the dealer on a regular basis as I have a lifetime oil service plan with my dealership. I can only assume they use 5W30 pennzoil.

I will post pics soon.

This is sounding like yet another systematic Mazda failure due to either poor material quality or inadequate engine management/protection systems.
it's strange how so many engines fail with no indication that a bad situation is pending like low oil level or fuel system malfunction which will eventually cause catastrophic engine damage.

Same would apply to the AC compressor failure problem which until now was the only significant problem I have had with my Mazda.

[devildoc]

Year: 2010
Make: Mazdaspeed 3
Model: Mazda
Damage: #3 piston through block
Miles: 34,500
Warranty: Yes(Until voided by mazda)

Repairs to be done: Pending
Mods: Fucking stock.
My warranty was voided because the dealership said that it looked as if whomever had the vehicle before me might have taken of the heatshield a nd possibly the turbo. Now i have a 3,00lbs paperweight. Thanks mazda

[Ziggo]

Do you really have a 2010 mazdaspeed? Not that I wouldn't appreciate a 2010 blowing up to prove to some idiots that their cars obey physics as well, but I doubt you bought a pre-owned 2010, and 34k is alot of miles for one year.

[R.MS3]

Could this be the first 2010 to blow up? Some people might laugh at this...

At what mileage did you get the car (you say it's been stock since then)? Oil change intervals? How did it happen?

[Amazon]

Originally Posted by devildoc Year: 2010 Make: Mazdaspeed 3 Model: Mazda Damage: #3 piston through block Miles: 34,500 Warranty: Yes(Until voided by mazda) Repairs to be done: Pending Mods: Fucking stock. My warranty was voided because the dealership said that it looked as if whomever had the vehicle before me might have taken of the heatshield a nd possibly the turbo. Now i have a 3,00lbs paperweight. Thanks mazda

A lot of miles for a year old car, and I don't buy that shit about them voiding your warranty because it "looks like someone removed the heat shield and maybe the turbo too at one time"

[dixie789456]

sounds like a shitty dealer or a lie. my heat shield and and all the silver heat shit was torn up and scratched to hell when i took mine in. i left the hks exhaust on too. they replaced my turbo.... no questions asked! i did make sure to line up the bolts on my down pipe so the blue paint on them lined up now when i take it in again.... if i have to then i can blame that shit on that guy who put the new turbo in. he really did a number on that silver heat shield crap down near the middle of the DP. worst dealer job ever! thats why i do my own fucking work.

[Tomas]

Originally Posted by scratchbuilt Hello all, I thought I'd toss my situation into the list of damaged rods. 2007 CX7 bought in August 2006, early production. No mods other than Forge BOV. Ok, here's a number for ya, 180,000 miles and the oil is changed by the dealership only and always between 3 and 7k. Situation: Driving to work in the morning @ approx 65mph and accelerating to pass a slower vehicle when the engine started ticking loudly. It never sounded any better or worse during the remainder of my drive to work. (35miles) The oil level did not register on the dipstick when checked upon arrival. I had about 4k on this oil change. Where did the oil go?????? I added new oil to top off and the ticking remained. Even after adding about 4 quarts, the remaining oil was so black it made the new oil as black as night as well. Damage: #3 connecting rod bent and damaged piston when it bottomed out against the crank. All pistons have hard crusty deposits around the rings and skirts. Bad oil or over heated pistons? As I said before, the oil gets changed by the dealer on a regular basis as I have a lifetime oil service plan with my dealership. I can only assume they use 5W30 pennzoil. I will post pics soon. This is sounding like yet another systematic Mazda failure due to either poor material quality or inadequate engine management/protection systems. it's strange how so many engines fail with no indication that a bad situation is pending like low oil level or fuel system malfunction which will eventually cause catastrophic engine damage. Same would apply to the AC compressor failure problem which until now was the only significant problem I have had with my Mazda.

Sorry about your rod saying bye bye.
On the other hand, I don't think I've heard of one of our engines lasting that long yet. 180K is a pretty good number.

Why there wasn't any oil in the pan could be due to different reasons. Just speculating, but if there aren't any visible leaks it could be the seals on the turbo passing oil. But it could also be low compression or bad valve guides. Any oil residue in the exhaust? Did you smoke at all?

[scratchbuilt]

Originally Posted by Tomas Sorry about your rod saying bye bye. On the other hand, I don't think I've heard of one of our engines lasting that long yet. 180K is a pretty good number. Why there wasn't any oil in the pan could be due to different reasons. Just speculating, but if there aren't any visible leaks it could be the seals on the turbo passing oil. But it could also be low compression or bad valve guides. Any oil residue in the exhaust? Did you smoke at all?

That's what is so confusing. There were no obvious leaks or smoke...
UPDATE: I just finished the bottom end with new pistons and rods that I got off of ebay from a MS3 build($375 for the whole set...NEW! with rings).I'm now getting ready to reassemble the rest of the engine. I think I had a lot of blow by because the area around the rings was really crusty and the bottom oil rings were clogged with hard polymerized oil. I can see crusty buildup on the skirts as well. I guess it makes sense with so many miles. I'm now going to replace the timing chain and the VVT actuator as they seem prone to failure as well. MazdaPartsSource has better than average prices on OEM parts so I went with them for my replacement stuff.
Prior to the rod failure I was getting the random misfire CEL when at WOT in 4th-6th gears.
I could really feel the engine hesitating but if I back off a bit the hesitation would go away. could this be a sign that something was going to go kablooie? I noticed this hesitation after I changed the spark plugs but not too sure if it's related.
Could it be that an injector was hanging open at times thus causing a hydraulic condition?

Whet is the most common cause of the bent/broken connecting rod without any mechanical evidence of impact? i.e. detonation or hydraulic forces.

[Lex]

Originally Posted by scratchbuilt That's what is so confusing. There were no obvious leaks or smoke... UPDATE: I just finished the bottom end with new pistons and rods that I got off of ebay from a MS3 build($375 for the whole set...NEW! with rings).I'm now getting ready to reassemble the rest of the engine. I think I had a lot of blow by because the area around the rings was really crusty and the bottom oil rings were clogged with hard polymerized oil. I can see crusty buildup on the skirts as well. I guess it makes sense with so many miles. I'm now going to replace the timing chain and the VVT actuator as they seem prone to failure as well. MazdaPartsSource has better than average prices on OEM parts so I went with them for my replacement stuff. Prior to the rod failure I was getting the random misfire CEL when at WOT in 4th-6th gears. I could really feel the engine hesitating but if I back off a bit the hesitation would go away. could this be a sign that something was going to go kablooie? I noticed this hesitation after I changed the spark plugs but not too sure if it's related. Could it be that an injector was hanging open at times thus causing a hydraulic condition? Whet is the most common cause of the bent/broken connecting rod without any mechanical evidence of impact? i.e. detonation or hydraulic forces.

The misfire could certainly be spark plug related. The motor is quite sensitive to spark plug gapping. The hesitation could also be a result of detonation causing the knock sensor to severely pull timing.

The most common failure for these cars is detonation after an extended cruise followed by loading the motor. Many people experience this and this is why most cars die/bend rods on the highway.

There has been some speculation regarding the true root cause but it appears to be related to combustion chamber overheating and the generation of hot spots.

Poor lubrication is also an issue with the DISI motor as oil gets diluted with fuel very quickly and the high combustion heat/poor ring design cause clogging of the rings and blowby. I change my oil every 3k miles with a full synthetic.

Did the rod actually break or was it just bent? Post up some high res picture of what the 180k rod/piston look like and focus on the rings and crowns of the pistons.

[hnda etr]

I popped... story here: Hnda Etr Blows... - Mazdaspeed Forums

[Tomas]

Originally Posted by scratchbuilt That's what is so confusing. There were no obvious leaks or smoke... UPDATE: I just finished the bottom end with new pistons and rods that I got off of ebay from a MS3 build($375 for the whole set...NEW! with rings).I'm now getting ready to reassemble the rest of the engine. I think I had a lot of blow by because the area around the rings was really crusty and the bottom oil rings were clogged with hard polymerized oil. I can see crusty buildup on the skirts as well. I guess it makes sense with so many miles. I'm now going to replace the timing chain and the VVT actuator as they seem prone to failure as well. MazdaPartsSource has better than average prices on OEM parts so I went with them for my replacement stuff. Prior to the rod failure I was getting the random misfire CEL when at WOT in 4th-6th gears. I could really feel the engine hesitating but if I back off a bit the hesitation would go away. could this be a sign that something was going to go kablooie? I noticed this hesitation after I changed the spark plugs but not too sure if it's related. Could it be that an injector was hanging open at times thus causing a hydraulic condition? Whet is the most common cause of the bent/broken connecting rod without any mechanical evidence of impact? i.e. detonation or hydraulic forces.

As stated before there are a bunch of different theories out there. But one thing is pretty certain. The most frequent cause of engine failure on these engines is conrod failure. Whether its from creep, low cycle fatigue, pre ignition etc it's all theories at this point.

Since it looks like you are going to be keeping this car for a while, the first thing you need to do after your build is to get you a monitoring device such as a dashhawk or other to monitor knock retard (KR). To start of, anytime you see KR of more than 1 at WOT in high RPM ranges you can assume something is not right.

What spark plugs did you use when you changed them out? stock?
Do you have any mods at all?

[scratchbuilt]

Originally Posted by Tomas As stated before there are a bunch of different theories out there. But one thing is pretty certain. The most frequent cause of engine failure on these engines is conrod failure. Whether its from creep, low cycle fatigue, pre ignition etc it's all theories at this point. Since it looks like you are going to be keeping this car for a while, the first thing you need to do after your build is to get you a monitoring device such as a dashhawk or other to monitor knock retard (KR). To start of, anytime you see KR of more than 1 at WOT in high RPM ranges you can assume something is not right. What spark plugs did you use when you changed them out? stock? Do you have any mods at all?

Here's some pics from my iphone.
I changed the plugs to some autolite POS's which the guy at Kragen said was an alternate to the stock replacement. NOT!
I just ordered a set of Denso Irridium IVT20 (stock temp). I've been wanting to get the Dashhawk for awhile but never seemed to have the extra funds. I race RC so my pockets always get emptied quickly during racing season.
See my original post for details on the failure situation. engine is stock besides the Forge BOV (blue spring w/no shims)

[hnda etr]

Originally Posted by scratchbuilt Here's some pics from my iphone. I changed the plugs to some autolite POS's which the guy at Kragen said was an alternate to the stock replacement. NOT! I just ordered a set of Denso Irridium IVT20 (stock temp). I've been wanting to get the Dashhawk for awhile but never seemed to have the extra funds. I race RC so my pockets always get emptied quickly during racing season. See my original post for details on the failure situation. engine is stock besides the Forge BOV (blue spring w/no shims)

I'm guessing this is what mine are going to look like... Did your cylinder wall(s) have any damage? I'm hoping not and I hope mine don't either...

[FreeFlyFreak]

Originally Posted by scratchbuilt Here's some pics from my iphone. I changed the plugs to some autolite POS's which the guy at Kragen said was an alternate to the stock replacement. NOT! I just ordered a set of Denso Irridium IVT20 (stock temp). I've been wanting to get the Dashhawk for awhile but never seemed to have the extra funds. I race RC so my pockets always get emptied quickly during racing season. See my original post for details on the failure situation. engine is stock besides the Forge BOV (blue spring w/no shims)

WOW!
You got lucky there.
Of all the pics I have seen of bends, that is by far the most bent rod that hasnt let go.
Im pretty sure i have seen some pics of broken rods that looked straighter that that.

[Tomas]

Originally Posted by scratchbuilt Here's some pics from my iphone. I changed the plugs to some autolite POS's which the guy at Kragen said was an alternate to the stock replacement. NOT! I just ordered a set of Denso Irridium IVT20 (stock temp). I've been wanting to get the Dashhawk for awhile but never seemed to have the extra funds. I race RC so my pockets always get emptied quickly during racing season. See my original post for details on the failure situation. engine is stock besides the Forge BOV (blue spring w/no shims)

Well, glad you got a good deal on your new rod/piston combo. Looks like besides the hours you 're going to put into the job, you're not going to be too deep in the hole after all this.

While you are at it you should also install an oil catch can between inlet manifold and crankcase. If you want, you can also install one between valve cover and turbo inlet pipe. Just watch out the can doesen't freeze shut in the winter and drain often at the beginning to see how much your engine blows by. Especially while you break in the engine you'll probably have more blow by than normal till the piston rings set in. It's an inexpensive add on that will prevent a lot of that soot you're finding everywhere from sticking to your internals.

What kind of RC do you race? If your spending that much money on it you must be pretty serious. I always thought a g or two could get you the best shit there is. Used to have 2x Graupner catamarans with servo actuated trim flaps, water cooled blue heads and all kinds of other shit. Long time ago. But it was a ton of fun. Been thinking about getting something again but I spend most free time modding the car and taking it to the track. And that can REALLY get expensive- fast. Problem is once you start you can't stop.

[scratchbuilt]

Originally Posted by Tomas Well, glad you got a good deal on your new rod/piston combo. Looks like besides the hours you 're going to put into the job, you're not going to be too deep in the hole after all this. While you are at it you should also install an oil catch can between inlet manifold and crankcase. If you want, you can also install one between valve cover and turbo inlet pipe. Just watch out the can doesen't freeze shut in the winter and drain often at the beginning to see how much your engine blows by. Especially while you break in the engine you'll probably have more blow by than normal till the piston rings set in. It's an inexpensive add on that will prevent a lot of that soot you're finding everywhere from sticking to your internals. What kind of RC do you race? If your spending that much money on it you must be pretty serious. I always thought a g or two could get you the best shit there is. Used to have 2x Graupner catamarans with servo actuated trim flaps, water cooled blue heads and all kinds of other shit. Long time ago. But it was a ton of fun. Been thinking about getting something again but I spend most free time modding the car and taking it to the track. And that can REALLY get expensive- fast. Problem is once you start you can't stop.

I just wanted to say "Thanks" for all the input, guys.
I did get really lucky with this one, especially after reading so many nightmares in these forums. Same goes for the AC compressor seizing up as I noticed smoke coming from the engine bay and managed to track it down to the compressor before any further damage occurred. So anyhow there is no damage to the cylinders or head. Actually there is a small ding at the very bottom of the #3 sleeve where the rod touched and it shouldn't hurt anything going forward.
I was wondering why I keep seeing the catch cans for sale all over? I think it would be a good idea too. I initially thought this was reserved for performance engines then after reading about the MZR more in depth, I realize that it IS a performance engine, even stock!
I'm not worried about the freezing issue as I live in Cali.

Now for the RC thing... I'm trying to limit myself to just 1/8 scale on-road Nitro and electric Touring Cars but I have also been developing an 1/8th scale electric conversion for on-road cars as well. It get's a bit costly to stay competitive as with any form of racing. Always gotta have the latest and greatest.

Once again, THANKS!

[Lex]

Originally Posted by scratchbuilt Here's some pics from my iphone. I changed the plugs to some autolite POS's which the guy at Kragen said was an alternate to the stock replacement. NOT! I just ordered a set of Denso Irridium IVT20 (stock temp). I've been wanting to get the Dashhawk for awhile but never seemed to have the extra funds. I race RC so my pockets always get emptied quickly during racing season. See my original post for details on the failure situation. engine is stock besides the Forge BOV (blue spring w/no shims)

That is a serious bend and it seems to be on more than a single axis. The rod is bent and twisted.

Were you at full boost when the ticking happened? Did you see a big screen of smoke behind you?

Perhaps the prior misfire was actually detonation - hard to tell without a DH or monitoring device

[scratchbuilt]

Originally Posted by Lex That is a serious bend and it seems to be on more than a single axis. The rod is bent and twisted. Were you at full boost when the ticking happened? Did you see a big screen of smoke behind you? Perhaps the prior misfire was actually detonation - hard to tell without a DH or monitoring device

Hey Lex,
The CX7 supposedly is at full boost past 2500 RPM so I suppose I'm always on boost.
Anyhoo, I was just crooooozing at about 65-70mph and accelerated to pass another car (not WOT) and then instantly the ticking started. no surge or bang and no smoke that I noticed.
one thing i've been thinking about is that maybe having the boost come on so low in the RPM range is not so safe for the rods. Since the CX7 is also AT only, perhaps it invites detonation while the tranny computer tries to figure out what to do when the accelerator is pressed harder. (this is really the thing that bugs me the most about the CX7 drivetrain).
I have an old Acura RS as a loaner while I fix my engine and this old boat always seems to find the right gear when I get back on the gas and it does it quickly. Go figure...

Perhaps I shouldn't have been racing that 911 Carrera the night before the rod bent?

[Lex]

So you're saying there's more to the story? The rod was tweaked before the major bend happened. Did you often get stumbles when you got on it after a highway cruise?

[Tomas]

I would actually say the AT is better than manual. On manual you can strees the rods at low rpm's for longer than auto. With auto the tranny shifts to higher gear if torque passes a certain point.

[scratchbuilt]

Originally Posted by Lex So you're saying there's more to the story? The rod was tweaked before the major bend happened. Did you often get stumbles when you got on it after a highway cruise?

Well, I can't say that it's related because the car was running fine in the morning prior to the tweak. I had only been driving for about 10 minutes, on my way to work when the ticking started. As you can see from the underside of the piston in the pics, there are grooves ground into the piston, just below the wrist pin, from the crank lobe and the balancer gear. This impact is most likely what breaks the con rods after they bend because the piston immediately gets slammed by the crank lobe. I think I got lucky that it didn't quite bend enough to hit the wrist pin which would be much harder to deform than a bit of aluminum.

I never really noticed any problems after a long highway stint (consider my mileage, I drive a lot of highway miles) but maybe that's a product of having an AT. I just had the surging at WOT after changing the plugs. I should clarify that the surging didn't happen in the lower gears. It was mainly isolated to 4th,5th and 6th. perhaps because of boost and loading differences.

I hope that all this discussion will somehow help other readers as to the situations that can lead up to a catastrophic engine failure like so many of us have experienced. Maybe we will find a common failure mode that can be avoided. Who am I kidding, it's just fun to bitch about stuff.

[Lex]

Load is greatest on the motor in the higher gears. So the gremlins come out of the woodwork at that point. Without a doubt the ticking you heard was from the piston hitting the counterweight. Then you lost a lot of oil through blowby.

The big question is - was there damage to the rod prior to this or was this a one-time event that caused all the damage that morning?

[Frequentflyer]

Originally Posted by scratchbuilt Here's some pics from my iphone. I changed the plugs to some autolite POS's which the guy at Kragen said was an alternate to the stock replacement. NOT! I just ordered a set of Denso Irridium IVT20 (stock temp). I've been wanting to get the Dashhawk for awhile but never seemed to have the extra funds. I race RC so my pockets always get emptied quickly during racing season. See my original post for details on the failure situation. engine is stock besides the Forge BOV (blue spring w/no shims)

so you're attributing the blown engine on cheap plugs? I've been running these plugs for 25k miles without issues.

[Ckmazdaspeed3]

Originally Posted by devildoc Year: 2010 Make: Mazdaspeed 3 Model: Mazda Damage: #3 piston through block Miles: 34,500 Warranty: Yes(Until voided by mazda) Repairs to be done: Pending Mods: Fucking stock. My warranty was voided because the dealership said that it looked as if whomever had the vehicle before me might have taken of the heatshield a nd possibly the turbo. Now i have a 3,00lbs paperweight. Thanks mazda

This guy is full of shit. I am on my iPad so I will double post the link in a sec, but here is what he said in a different thread... Sorry if someone has pointed this out, but I didn't see it.


I have an 2010 MS3. i put on a COBB SRI, Turbo inlet, Downpipe and Racepipe. Everything was cool until i put on the downpipe then, i got the infamous P0171 for about two weeks, then sputtering and power loss at high boost. Today i got a burning smell, no power, knocking at idle and loud knocking when i push my my clutch in. WTFO? Anyone know WTF is going on? i dont race my car at all, just daily drive. Is this happening to anyone else?

Doesn't sound too stock to me. And I haven't run across cels yet (don't have that many mods), but I think I would do something if I got an "infamous p0171"... Assuming that is bad.

Originally Posted by Ziggo Do you really have a 2010 mazdaspeed? Not that I wouldn't appreciate a 2010 blowing up to prove to some idiots that their cars obey physics as well, but I doubt you bought a pre-owned 2010, and 34k is alot of miles for one year.

I just had to do some research because I want to live under the illusion that as long as we follow all the rules that you gen one guys have passed down (HPFP, monitoring, no wot below 3+k...) our cars won't obey the law of physics...

Here is a link to the post where he listed his mods and his previous problems.

http://www.mazdaspeedforums.org/foru...ly-slow-63771/

[scratchbuilt]

Originally Posted by Frequentflyer so you're attributing the blown engine on cheap plugs? I've been running these plugs for 25k miles without issues.

I'm just saying that the random misfire started after I change to these plugs.
Whether or not they contributed to the bent rod, I can't say for sure.
Perhaps over time the misfire weakend the rod. Dunno...

[Amazon]

Originally Posted by Ckmazdaspeed3 This guy is full of shit. I am on my iPad so I will double post the link in a sec, but here is what he said in a different thread...

Good eye Ck, full of shit he is



I bet he kept ragging on it even though his poor stock pump was crying for mercy. No sympathy for this retard.

[scratchbuilt]

Hey all,
I got the motor back together and it's running really good. I've already got about 900 miles on the rebuild with no leaks or problems to speak of.
I decided to check all of the tappets for wear and sure enough, they were all under their indicated thickness.
Some more than others but still in need of replacing. I had to bite the bullet and reinstall them as is for the time being. I managed to log all the gaps and tappet thickness in a Excel spreadsheet so I will be able to order up some replacements for later.

[2007Atenza]

We recently purchased a Speed6 from a used car dealership in Cayuga, Ontario. We were unaware of the history of the vehicle other than: powersteering line under warranty and minor fender bender. The car was off-lease and when purchased had 98,000 km.

After 3 days of driving, we had a severe mis-fire under load and boost. It was brought back to the used car dealer. They upgraded the spark plugs as this was "the problem".

When we got the car back, it seemed the mis-fire was resolved. However, approximately 2 days later, the check engine light came on under load and boost. The car was brought back to the dealership and the code was read. The dealership said it was a "turbo problem". They advised me to keep it under 4000 RPM and they booked it to come back in 2 weeks.

The check engine light eventually went away but reappeared under cruising conditions on a downgrade hill (50 km/h). The light went away again.

1 day later, at cruising speed of 90 km/h in 6th gear, the engine blew up. It was towed to the dealership and left for them to find in the morning. Upon diagnosis and inspection, the mechanic revealed that the waste gate malfunctioned and was stuck closed. #3 connecting rod broke and blew through the front and back of the block, taking out the oil pump and pan with it.

2 weeks later we get the car back. They replaced the engine with a used engine with 78,000 km. The check engine light re-appeared but the car does not have any noticeable stutter. We brought the car to a local garage (friend) and found the vacuum line to be faulty and needing replacement.

We thought this would be the end of the problems but yet again, the check engine light is on. It sometimes goes off but reappears under load and boost conditions. The car is currently in the shop.

Car: 2007 Mazdaspeed 6
Cylinder: #3
Damage: Tossed rod. Hole at front & back of block, oil pump & oil pan destroyed.
RPM: 2500-3000
Mods: Stock, however we don't know if the previous owner had mods that were removed before returning on lease.
Exhaust Manifold: Stock
Situation: 6th gear cruising at 90km/h on a flat highway
Warranty: 3rd party
Oil: Level was OK

[802MS3]

lol the first motor died a horrible death. The second one will too unless you get that thing to someone who knows these cars. the dealer is obviously retarded and doesn't know how to deal with the symptoms you are describing. Also, make sure you put the highest octane fuel in it that is available to you.

[Tokay444]

I've just picked up an 07 off lease with 80,000kms on it, and it seems to be mint and very strong. When I first picked it up, I was very surprised at all the torque down low, coming from hi revving hondas. Occasionally I'd floor it from about 2000rpms in 6th on the highway and just enjoy the low end torque whoosh. On one or two occasions, I had a slight miss. I let off immediately noticing that the car did not like that. I've adjusted my driving considerably. Now after reading this thread, I fear I may have already done some damage. The misses weren't huge, and it was only ever one. Never multiple jerks. Should I be worried? I'm almost a little nervous to take it on the 2600 kilometre round trip to NC we have planned for the summer. Is there anything I can check, short of getting to the rods to see if they've suffered any ill effects from my ignorant misuse?
Edit* I should add, the car is bone stock, aside from the sure RMM I isntalled a couple weeks ago with great results. I run 94 octane religiously, and it's averaging -10c right now. I'm guessing after I get my koni sports, I should look at a meth kit to keep everything cool this summer. Would colder plugs be beneficial on a stock car?

[R.MS3]

Just get a compression test done to check the motor's health. Also make sure the car is not smoking from the exhaust at idle (usually an indication of a bad turbo) or anything like that. Black smoke under heavy acceleration is fine and it's to be expected (car runs rich at WOT).

[Amazon]

Originally Posted by Tokay444 Occasionally I'd floor it from about 2000rpms in 6th on the highway and just enjoy the low end torque whoosh.