DISI Compression Results

[gsrtype1]

Been meaning to tell u guys I rented a brand new gauge still in plastic couple weeks ago. I got 100-105 in cylinders 1,2,4 and 85 in 3. I don't think those # are accurate that other gauge I had was leaking and reading 180, lesson learned? don't trust those dang gauges. I saw an auto tv show that said the same thing. All gauges read different.

Originally Posted by cpolly69 140 is the min i believe - they are also looking for a 40lb difference in between any 2 cylinders iirc

The shop manual sais 129 lowest acceptable and know more than a 28.5psi variance.

[cpolly69]

sorry joe,
been a while since i looked at that page in the fsm - i was all over it back in december
the real question is, could that cat get any fatter??

[gsrtype1]

Originally Posted by cpolly69 sorry joe, been a while since i looked at that page in the fsm - i was all over it back in december the real question is, could that cat get any fatter??

haha actually bro his fur just makes him look fatter. He is fat butt twitch in my sig actually weigh's more than big oranger lol...

[shpankey]

Yeah I had read the 129 somewhere also. So if mine is 130 (which it is, every time) are they going to say no can do? Over a silly 1 psi? That would be the shits. Have to pay them $200 and lose my car for another week b/c of 1 psi. I honestly don't know what to do now. All cylinders are reading dead on 130psi. Every single time.

[8.5MS3]

how close are you to the dealer?

drive to a spot close by.

go have lunch and let the engine cool down

get to the dealer quick and do a comp test while ECTs are normal, but the block is still relatively cool

cold motor = lower compression. usually you need to go for a nice 15 min drive to bring the metal up to full operating temps

[byau]

you might've already answered this but have you tried a different gauge?

[cpolly69]

dealer is not going to want to just do one test and say - hey's its low get this guy a new motor - that's not how it works - trust me i know
first u have to describe to them the symptoms of lost compression - i.e. i'm down on power or my car is smoking -
then you have to sit around and let them make judgments on their own - u can't just go in and demand they do a compression test - if u do - u will pay for the test
there has to be a diagnosable chain of events that leads to you having lost compression and you have to convince people
btw if you are gonna start that battle - don't show up if you have flashed your ecu and don't show up if you have any mods - stock out
also be sure to bring every oil change record you have - to show a solid history of oil changes

[shpankey]

I'm %100 stock now. Never flashed my ECU, ever. I didn't have but a few small mods, intake, motor mount, shifter bushings, etc. They are all back to stock. The car has been in since then, they did the shifter fix under warranty. They already seen all my oil change receipts (I'm an oil super fan, I buy tons and TONS of it). They even commented how much oil I have. lol So I'm all good on that front.

I told them about the power loss, and in my mind it's absolutely dramatic. But their "tech" drove me car and told them it drives like every speed 3 he's driven before. They had logged over 10 miles on the car so I'm assuming he went hot rodding to test it out (how else?). Which I'm not sure if I appreciate. lol

[rudeboy3]

I was changing my spark plugs back to stock today so I decided to do a check. Cylinder 3 almost proved to be a heart breaker at 160, but I didn't crank as long as the others. It too tested at 170 the second time. My MS3 has 25 000 miles and change with no mods. I made sure the engine turned over six times before checking each cylinder. Car was fully warmed up.

Originally Posted by shpankey I'm %100 stock now. Never flashed my ECU, ever. I didn't have but a few small mods, intake, motor mount, shifter bushings, etc. They are all back to stock. The car has been in since then, they did the shifter fix under warranty. They already seen all my oil change receipts (I'm an oil super fan, I buy tons and TONS of it). They even commented how much oil I have. lol So I'm all good on that front. I told them about the power loss, and in my mind it's absolutely dramatic. But their "tech" drove me car and told them it drives like every speed 3 he's driven before. They had logged over 10 miles on the car so I'm assuming he went hot rodding to test it out (how else?). Which I'm not sure if I appreciate. lol

I hate the fact they make it so difficult. I had a brutally rough idle and it took three visits with persistent politeness until they cleaned the egr. Same thing: They test drove it twice and concluded that the car ran like a champ until they eventually conceded that it needed attention. Don't give up and keep repeating that your power is way down, stumbles etc.: I hope it works out for you.

[shpankey]

Just an update. Also need some advice. Last night, I finally got around to getting another compression tester. I borrowed one from O'Reilly's. After a long drive, car was warmed all the way up. I did the test again. My new Amazon bought compression tester once again read 130psi across all cylinders. Then I used the O'Reilly's one. Please someone tell me what this means...

After cranking the engine over 6 times... it would read 150psi on all cylinders. But it was still climbing rapidly with each crank over.

But if I kept letting it crank to 12 or 13 times, it would go just above 180psi on all cylinders. That's the max it would go to no matter how long I let it crank.

So my question is, what is my reading? Is it 150psi or 180psi?

[cpolly69]

it's 180 and as long as that's what it is on all 4 u are fine

[shpankey]

YES!!!!!!!!

Thank you sir! Whew... I cannot tell you how much this has been weighing on me. To think your car is fubar'd is hard to deal with. In this case, this car is my BABY. lol

[*Scotsman*]

Glad I found this thread and the advice in it. A little history about my situation:

I had the VVT TSB done on my car about 3K ago when the car was at 55K. Mazda shared in some of the cost since it was a known issue and I had it in several times before the warranty was up, but I still had to lay out $700 to get it and other things fixed.

About 2 weeks later while on the highway, I had to get out of the way of an idiot in a hurry, so I gave it some gas while in 6th. My DH lit up like a christmas tree with KR, so I immediately let off the gas put the clutch in. At the same time, I was thinking "Oh shit, did I just bend a rod?" Since that incident, I was seeing KR more frequently and higher, so I was really nervous about the engine condition.

After reviewing some posts, I decided to try going with 1 step colder plugs. I did that, but I didn't see a huge reduction in KR. Of course, I couldn't find the compression test thread until after swapping plugs, because that would have been too easy.

Last night, I went to Autozone to rent their compression tester. Hmm, thought it was free, but they told me it was $38 to rent. After seeing it, I decided it looked like a POS, so decided to buy one. They had one for $49, but it had about 2" of dust on it with very few adapters, so I took a stroll across to Sears. Picked up a nice one for $65 with all the adapters that I could every think of needing.

Did the test this morning after warming car for 15-20 minutes:

Pass side
#1 185
#2 180
#3 185
#4 190
Driver side

Sigh of relief ^^^

Just for good measure, test #2:
Pass side
#1 180
#2 180
#3 175ish
#4 180
Drivers side

^^^ Huge sign of relief!

Re-checked gap on 1-step colder plugs. 1 was way off at approx .034, so re-gapped all of them to .028, as I am getting a Cobb AP soon.

My car: '06 Speed6 with 58K miles, Cobb SRI, AWR RMM, JBarone SSP and bushings, Magnaflow CBE, Hypertech tuned, 1-Step colder plugs and Dashhawk (to scare the shit out of me!)

[2007speed3]

^^ I thought it was free to rent as well. I thought they would charge you a fee then as you return it you would get your money back.

What was the difference between the first test and second? both warm engine/ cold engine etc?

[*Scotsman*]

I wouldn't have rented the one they had even if it was free....it looked nasty!

Difference between the 1st & 2nd test......about 5 mins!!!

I figured that since it was all pulled apart, I would just retest. Both were while the engine was warm, but presumably, the second was slightly cooler. :grin

[laxplayermjd]

i had 175 all four cylinders with 20 k on my ms6

[AutoXRacer]

I don't own a MS3 anymore, but before I got rid of my 2008 MS3 because my dip stick would blow out and shoot oil all over the engine bay, the dealer checked compression and it was within specs... Then they did a leak-down test failed majorly saying I needed a new engine...

Moral of the story, compression test (according to shops in general) does not tell you the whole story... The only and true test is leak-down.

At least thats what I've been told.

[djuosnteisn]

I wonder if a bad PCV and leaky intake valves could falsely indicate bad rings on a leak down.

[cpolly69]

Originally Posted by djuosnteisn I wonder if a bad PCV and leaky intake valves could falsely indicate bad rings on a leak down.

I've had this thought -
It has been proven that the factory pcv valve does leak and it is connected straight to the crankcase/im, but the pressure transfer as to what's going on inside the combustion chamber shouldn't be effected by what's going all the way out in that area...
As for the valves what happens with oil added should do a good job of indicating if this is the culprit.....
My 2 cents anyway

[djuosnteisn]

Well, don't they usually just listen for where the air leaks from when doing a leak down test? Like listen to the dip stick, if it's leaking... then it's rings. Or if it's coming out the IM, it's int valves... etc etc etc.

If the pressure leaked through gummed up int valves, through PCV, into CC and out dip stick, it could be falsely construed as rings when it's not.

I dunno, i'm just bored at this point....

[laxplayermjd]

well you guys are kinda right. Compression tests done tell you a whole lot. I did a leak down test as the same time as my compression. 175psi all four. leak down test showed 15% leakdown past the rings. this is a normal range.

To do the leakdown you pressurize the cylinder with 100psi air, based on what the gauges are showing thats the percent leakdown. you then need to find where its coming from. only three ways, well four ways it can leak. you listen into the exhaust, if you hear air coming out then you have leaking exhaust valves. Same goes for intake. Note that you can have gunked up intake valves and no air leak past them. The valve seat can be closed fully with gunked up valves. Im starting to get some build up on mine and no valves were leaking. I had leak down past the rings, i took the oil cap off and you can clearly hear the air rushing into it. A rare way for leak down would be between cylinders if the engine was over heated.

It would be hard IMO to misinterpret these readings. if it was leaking past the intake valves and through the pcv. you would still notice most of the air in the intake system and very minimal in the crankcase.


You can also test if your rings are worn by doing a wet compression test. Most are done dry as most people do. If you suspect rings are the issue and dont have leak down test. Put a few drops of oil in the cylinder and retest. The reading should be higher. If theres a huge difference between the two. the rings are most likely escessively worn

[Lex]

^ Or the rings are coked and seized no longer sealing.

[mo4130]

195 on all four. Initial pressure was 90 psi on the first crank. 37500 miles with a Sri test pipe ets tmic. Still smokes a little on idle. At least the engine is good.

[Tomas]

Getting ready to do a comp test.
I have been reading this thread from the beginning and it's been mentioned that if you have flashed the ECU not to bother going to the dealer for engine warranty work in case its needed.
How about if you have an AP, flash back the stock map, and "unmarry it" from the ECU? can they still find out if the ECU has been reflashed in the past?

[BigJimMs3]

When I had my 07 speed 3 at the shop about a month ago I asked if they could do a compression test and they did 180 in all four 07 with 30k at the time

[8.5MS3]

I unmarried my ap when I brought my car to the dealer for a new turbo. They scanned the ecu for trouble codes n whatever else, told me that they found nothing. That's not to say if they really wanted to dive into the bowels of the software they wouldn't find anything. But for general purposes, no they can't detect it.

[Tomas]

Originally Posted by 8.5MS3 I unmarried my ap when I brought my car to the dealer for a new turbo. They scanned the ecu for trouble codes n whatever else, told me that they found nothing. That's not to say if they really wanted to dive into the bowels of the software they wouldn't find anything. But for general purposes, no they can't detect it.

ok, good. I am bolted except for DP running ATR and will keep it that way then.

[leo766]

Originally Posted by wassup61 Uhh... here is the procedure for comp test. 1. beat shit out of car to warm up 2. come home and pull plugs 3. depress clutch AND gas all the way to the floor and crank 5-8 times (will keep injectors from firing and open throttle plate). 4. Measure compression per cyl. 5 charge battery. I have 8.8:1 arias, after beating on it and getting it hot i comp tested 183,182,184,187, which is high for a low comp. motor.

note the underlined... i wonder how this genius starts his car in the morning? cuz u do know that "starting" the car is step 3, its just that by pulling plugs ur making sure the fuel ur dumping into ur exhaust is pooling up, ready to blow the insides of your cat all over your drive way lol

also beating the shit out of your car to warm it up is the dumbest idea, i bet this guy has, or is going to have a smoking turbo in no time, since just cuz its a water cooled turbo, doesnt mean the oil is pumping through it full speed, even if you coolant temp guage says so(guage reads even at 160... noticeable performanc gain in keeping it around 190-200 for me personally which takes about 5 more min after the temp guage reads even which seems to mean that ur temp is 160-220)

anyways, pull fuel relay fuse, same as the HPFP rmoval procedure, then crank the car to make sure it doesnt start or starts and stalls

thats it... why not do it te right way? and not make ur exhaust into a 5th cylinder

i honestly think people are just afraid of pulling relays cuz they dont get that its not some scary device, and works much like a fuse, that and poor instructions



well im done with my 6am morning b!tch!ng

[cpolly69]

The factory service manual is usually a good place to start looking for a proper compression test procedure. Internet cliff notes will almost always get you a hand full of fail.


Sent from my iPhone using Tapatalk

[shpankey]

Originally Posted by leo766 note the underlined... i wonder how this genius starts his car in the morning? cuz u do know that "starting" the car is step 3, its just that by pulling plugs ur making sure the fuel ur dumping into ur exhaust is pooling up, ready to blow the insides of your cat all over your drive way lol also beating the shit out of your car to warm it up is the dumbest idea, i bet this guy has, or is going to have a smoking turbo in no time, since just cuz its a water cooled turbo, doesnt mean the oil is pumping through it full speed, even if you coolant temp guage says so(guage reads even at 160... noticeable performanc gain in keeping it around 190-200 for me personally which takes about 5 more min after the temp guage reads even which seems to mean that ur temp is 160-220) anyways, pull fuel relay fuse, same as the HPFP rmoval procedure, then crank the car to make sure it doesnt start or starts and stalls thats it... why not do it te right way? and not make ur exhaust into a 5th cylinder i honestly think people are just afraid of pulling relays cuz they dont get that its not some scary device, and works much like a fuse, that and poor instructions well im done with my 6am morning b!tch!ng

I agree with you about not beating on a car to warm it up. Very stupid. One should wait till oil is at operating temp before anything serious. But the guy is right about pushing the gas pedal down to close the throttle plate being sufficient. Pulling the HPFP fuse is not a necessity if doing this.

[08_ms3_gt]

Originally Posted by 08_ms3_gt did a compression test tonight; 2008.5 mazdaspeed3, 35,000 miles (literally) cylinder pressures: (pass side) cyl 1 - 182psi cyl 2 - 177psi cyl 3 - 175psi cyl 4 - 178psi (driver side) b/c i was doing the test alone, i'm actually pretty sure all of the pressures were around 180-185. the reading was declining before i even got from the inside of the car to the engine.

did a new compression test this week - 49,670 miles.

(pass side)
cyl 1 - 179psi
cyl 2 - 179psi
cyl 3 - 179psi
cyl 4 - 179psi
(driver side)

the results are more consistent probably because the testing was more consistent - i was sure to max the pressure on the gauge, then jumped from the driver's seat to the engine bay to read it.

from these results, it would appear as though my cylinder #3 is okay, and the pressures have decreased maybe a little bit (if it all) in 15,000 miles.

[shpankey]

08_MS3_GT how many cranks did you do on them?

[08_ms3_gt]

probably around 10. i think it took less than 10 to max the pressure, but i wanted to be sure.

[shpankey]

Thanks. Experts... what does it mean when it takes me 17 to 20 cranks to reach 180psi?

[Lex]

Originally Posted by shpankey Thanks. Experts... what does it mean when it takes me 17 to 20 cranks to reach 180psi?

Can't say much without more testing ... if it reaches 180psi you can just call it a day and sleep well or worry about it some more and do a leakdown test.

I would do the former.

[08_ms3_gt]

You may have a bad tester, or a bad battery. 20 is a lot, but I'd go with what Lex said.

[turboneil]

I've heard that you should hit about 100psi on the first crank. So if it does that hen I wouldn't worry about it.

[shpankey]

Thanks. The battery is great actually. My first crank hits like 50 - 70 psi usually. I honestly think my performance loss has came from dirty intake valves now as there's nothing wrong with the car at all as far as starting or driving, other than the power loss. I don't burn oil. In fact, I don't even smoke. Car starts right up. 27k miles now and it runs great other than the power loss. This is why I looked at the compression in the first place.

I should add more to the story though. I bought a brand new compression tester from amazon. Supposedly one of their best ones. Has a million adapters. And with this tester I hit 150psi across the board. Doing a wet test gave me a bit more psi but not 180. Then, using the advice given here, I borrowed a compression tester from a local parts store to test it again and that one gave me 180 psi across all cylinder's... so I took it the one from amazon was just miscalibrated or bad or something. I can't really afford a leakdown test right now so I'm just kind of doing what Lex recommended. The power loss is there and evident but it's still fairly fast car and I don't get on it much at all anyhow so I'm just driving it as is.

[Lex]

Originally Posted by shpankey Thanks. The battery is great actually. My first crank hits like 50 - 70 psi usually. I honestly think my performance loss has came from dirty intake valves now as there's nothing wrong with the car at all as far as starting or driving, other than the power loss. I don't burn oil. In fact, I don't even smoke. Car starts right up. 27k miles now and it runs great other than the power loss. This is why I looked at the compression in the first place. I should add more to the story though. I bought a brand new compression tester from amazon. Supposedly one of their best ones. Has a million adapters. And with this tester I hit 150psi across the board. Doing a wet test gave me a bit more psi but not 180. Then, using the advice given here, I borrowed a compression tester from a local parts store to test it again and that one gave me 180 psi across all cylinder's... so I took it the one from amazon was just miscalibrated or bad or something. I can't really afford a leakdown test right now so I'm just kind of doing what Lex recommended. The power loss is there and evident but it's still fairly fast car and I don't get on it much at all anyhow so I'm just driving it as is.

So you've had power loss? Have you been getting lots of blowby (oil in intake etc)?

[shpankey]

Yeah definite power loss. Very very noticeable. Not sure on the blowby. How do I check for that? You say oil will be in the intake? What do I take off to look in that? I know this sounds really dumb, but I'm not sure where the intake manifold is. lol. Or do you mean I should look in the air intake? I've had the air intake and TIP and TMIC off a few times but never noticed any oil anywhere. I also cleaned the EGR and EGR pipe at 12k miles with seafoam and carb cleaner and also took the hose off that goes to the throttle body and cleaned the throttle body. But on any of these, nothing was really ever very dirty or oily to be honest.

I've also cleaner the MAP sensor at 12k miles and I clean the MAF everytime I clean the air filter, so about 5 times so far, as I like to keep the air filter very clean. I also run synthetic oil's in everything, including transmission (XT-M5-QS) and power steering (Amsoil ATF) and brake fluid (Valvoline DOT 4 & 5 full synthetic) and oil (currently Edge 5w30, but have ran Redline, Royal Purple, German Castrol, Rotella T6 and Pennzoil Ultra European Formula). I've also changed the plugs a few times, as I tried some step colder Denso's, then step colder NGK Iridium IX's, but since have changed back to stock heat range OEM NGK Laser's, which are supposed to be exactly like the stock plugs, gap at .28 as the Denso's and NGK IX's fouled out early on me. I've also put a new PCV valve on it at 20k miles since I was already there messing with it (taking the OCC kit off) and broke the original by accident trying to get the OCC lines off. So I just put a brand new PCV valve back on it.

I took the OCC kit off (matt's) because it caused my car to smoke a bit. Another user here told me that happened to him to when he put an OCC on and it was due to something about CC pressure or some such. When I took the OCC off, it stopped smoking, just like he said, so I've left it off since then. I had it on for about 5k miles or so. It never collected all that much. Maybe a 1/4 of a cup, if that, every 6 to 7k miles. I figured this was due to using high quality synthetic oils.

Oh yeah, last thing, I Seafoam the car right before every oil change to try to help combat the intake valve issue. This seems to regain some of the power, but not all, each time, but it doesn't last long at all. Withing 150 to 200 miles the car goes right back to where it was. So I'm not sure how much this is really helping.