DISI Compression Results

['MERICA]

190, 185, 155, 190....... how bad is this? I tried reading the whole thread and im losing my train of thought...... ugh im nervous about this... any suggestions?

[Dano]

There is def something wrong in that 3rd cylinder. I would get a leakdown test to confirm but some possibilities, non of which are good are:

bent rod
broken piston ringland

do you get any vibrations when you press the clutch in?

['MERICA]

Originally Posted by Dano There is def something wrong in that 3rd cylinder. I would get a leakdown test to confirm but some possibilities, non of which are good are: bent rod broken piston ringland do you get any vibrations when you press the clutch in?

No there is no clutch pedal vibrations, the car runs great, no burning oil, still very strong pulls, i also am still getting great gas mileage as well... i have read in this thread the oil in plug hole test which i plan on doing tuesday... im hoping its a valve problem more than anything else

[theurgy]

Get a leakdown test done.

[NJSPEED3]

Originally Posted by Dano There is def something wrong in that 3rd cylinder. I would get a leakdown test to confirm but some possibilities, non of which are good are: bent rod broken piston ringland do you get any vibrations when you press the clutch in?

blown injector seal

['MERICA]

Originally Posted by theurgy Get a leakdown test done.

That was also on the checklist.. im feeling more confident its not a bent rod.. however if its the piston rings its still going to cost me :/... injector seal would be optimal problem lol

[theurgy]

Injector seals are my next install.

[MSMS3]

Late to the compression posting party, but here it is. 70,000 miles on '08 MS3, purchased new in May, 2008. Mods below. Drive it hard. Recently did the intake manifold valve cleaning (about two months ago). Full synthetic 5w-30 since first oil change. Altitude is 200 feet. Ambient temp was 92 degrees.

Did warm engine compression test last night out of curiosity. Forgot to pull the fuse on the injectors, so this is with some fuel being shot into the cylinders.

Facing engine left to right (passenger side to driver side)

#1 - 180
#2 - 180
#3 - 172
#4 - 180

I repeated #3 and got the same number. Have not done a leak down test, but I don't see 8 psi as a reason to be worried. It is something to watch and recheck. Original turbo. Never smoked. Did just have VVT and timing chain service done at dealer right before hitting 70,000. They did it free under warranty, even with my mods and no oil change records! I only flashed ECU back to stock for dealer service. Thought I'd get hit for $1200. I guess there may be some benefit from being 62 years old and not looking like the racer that i really am. lol.

[TWOptSL0W]

Originally Posted by TWOptSL0W just hit 50k and i have 180 in all cylinders i guess im good for another few miles until my shit explodes

70k...my shit exploded

[Dano]

lol @ zero compression in all cylinders.

[AtTheDriveIn]

~180 across. 81K.

[Tokay444]

@MSMS3 if you hold the gas to the floor while cranking, the injectors shut off.
Try it on your next startup.

[MSMS3]

^ Thanks! That is useful info. I intended to pull the fuse and just forgot. Will certainly follow your advice when I check compression again. I want to keep an eye on #3 and make sure it does not drop further in relation to the others.

[nextgenerationx1]

just picked up my 06 ms6, did a compression check b4 i purchased it, 175 down the board! @phate

[Lex]

Originally Posted by nextgenerationx1 just picked up my 06 ms6, did a compression check b4 i purchased it, 175 down the board! @phate

Sounds like you got one in good shape!

[Jh8909]

Did mine last night. Uh oh
(passenger)
175
150
125
175
(driver)

Looks like time to source a new motor!

[Lex]

Originally Posted by Jh8909 Did mine last night. Uh oh (passenger) 175 150 125 175 (driver) Looks like time to source a new motor!

Did you crank it until the needle stopped rising?

[Jh8909]

Originally Posted by Lex Did you crank it until the needle stopped rising?

Yep, even checked cylinder #3 twice. Consistent 125

[smoogs12]

Originally Posted by Jh8909 Did mine last night. Uh oh (passenger) 175 150 125 175 (driver) Looks like time to source a new motor!

Do a leak down test to find the source of the loss in compression. Its possible you might not need a whole new engine.

[franz]

I just did mine today. 83k on the motor.

170
160
165
165

I am pretty happy with the results.

[himurax13]

Originally Posted by Jh8909 Did mine last night. Uh oh (passenger) 175 150 125 175 (driver) Looks like time to source a new motor!

Any update on this?

[Jh8909]

Originally Posted by himurax13 Any update on this?

Yep.

[phate]

[QUOTE=Jh8909;1698256]Yep.

Brand spankin new from Mazda? I recognize that box lol.

[Jh8909]

[quote=phate;1698287]

Originally Posted by Jh8909 Yep. Brand spankin new from Mazda? I recognize that box lol.

Yep. Just tested to see if it works. Its got 3 miles on it. Got it for a steal. You don't wanna know how much lol

[phate]

[quote=Jh8909;1698334]

Originally Posted by phate Yep. Just tested to see if it works. Its got 3 miles on it. Got it for a steal. You don't wanna know how much lol

You're doing well if it was under $3500 or so

New shit runs SOOO well, lol. Have fun with it!

[Jh8909]

[quote=phate;1698385]

Originally Posted by Jh8909 You're doing well if it was under $3500 or so New shit runs SOOO well, lol. Have fun with it!

Well i got it from a guy that works at mazda down in maryland, traded him an AP and Autotechs for it. So $763 lol

[phate]

Originally Posted by Jh8909 Well i got it from a guy that works at mazda down in maryland, traded him an AP and Autotechs for it. So $763 lol

LOL, AWESOME!

[himurax13]

[quote=Jh8909;1698399]

Originally Posted by phate Well i got it from a guy that works at mazda down in maryland, traded him an AP and Autotechs for it. So $763 lol

Jealous.

[theurgy]

Seriously jealous.

[Dano]

Originally Posted by Jh8909 Well i got it from a guy that works at mazda down in maryland, traded him an AP and Autotechs for it. So $763 lol

that is redic....seriously!

good for ya

[Jh8909]

Yeah there is no rush to put it in now. I picked up a beater so I'm just gonna try to save up for now and then take it to pablo eventually and let him do his magic.

[kimura]

tested again after about 6k miles on the gt30

got the best results I've ever seen on any car I've owned lol

1 - 184
2 - 182
3 - 183
4 - 184

[aviator79]

Originally Posted by Dano lol @ zero compression in all cylinders.

That is what I am getting on two motors. Yet to test the one in my car. Looks like both motors the intake valves dont close until TDC. Could both be perfectly off 90* of time or whatever it is? First motor is a built engine and should be perfect. 2nd has 60k on it and should be good also. Seems like user error but I didn't think I was that stupid. Tested comp tester with compressor and can get it to go up to 60 or so.

Did someone else have the same problem? I assume that is what you were quoting. Didn't have time to read all 10 pages yet.

[smoogs12]

Originally Posted by aviator79 That is what I am getting on two motors. Yet to test the one in my car. Looks like both motors the intake valves dont close until TDC. Could both be perfectly off 90* of time or whatever it is? First motor is a built engine and should be perfect. 2nd has 60k on it and should be good also. Seems like user error but I didn't think I was that stupid. Tested comp tester with compressor and can get it to go up to 60 or so. Did someone else have the same problem? I assume that is what you were quoting. Didn't have time to read all 10 pages yet.

Hold on are you doing a compression test or a leakdwn test?

Edit; re read post. The part about the compressor is what confused me.

In that case, have you done a leak down?

Tapa

[aviator79]

Originally Posted by smoogs12 Hold on are you doing a compression test or a leakdwn test? Edit; re read post. The part about the compressor is what confused me. In that case, have you done a leak down? Tapa

Nowhere had a leakdown tester so have no way to do one yet. Both engines are on stands, not in car.

One tried with starter attached using a battery and got nothing for compression. I can look down spark plug hole on both and see that the valves stay open as cylinder comes up. This confuses me.

[Dano]

Originally Posted by aviator79 Nowhere had a leakdown tester so have no way to do one yet. Both engines are on stands, not in car. One tried with starter attached using a battery and got nothing for compression. I can look down spark plug hole on both and see that the valves stay open as cylinder comes up. This confuses me.

pull the oil fill cap and see if the timing chain is moving when you turn the motor over...if not the crank bolt/washer combo is fubared...turn the motor by hand not with a starter.

[aviator79]

Originally Posted by Dano pull the oil fill cap and see if the timing chain is moving when you turn the motor over...if not the crank bolt/washer combo is fubared...turn the motor by hand not with a starter.

Timing chain is moving, valves are moving. Anyone ever check compression when engine is out of car?
I just got 30psi on cylinder 1.

[smoogs12]

Originally Posted by aviator79 Timing chain is moving, valves are moving. Anyone ever check compression when engine is out of car? I just got 30psi on cylinder 1.

I feel like given your situation, a leak down test would really be better.



Tapa

[Dano]

Originally Posted by aviator79 Timing chain is moving, valves are moving. Anyone ever check compression when engine is out of car? I just got 30psi on cylinder 1.

never have...and to get an accurate compression or leakdown test the motor needs to be at operating temp which you cant duplicate with it out of the car. I wouldn't think it would be that low even stone cold. maybe 150 where warmed up it would be 180.

[ms3blackmica]

Very cool thread!

Here are my results. I did not pull all the spark plugs (did one at a time). I'll do it again with all plugs removed. Gotta nag my friend to let me get that snap on tester back !

205
200
200
200