Got my compression TEST

[vd96TALON]

So finally I got them

1 - 115
2 - 112
3 - 110
4 - 110

Seems abit low to me, what do you guys think? (my car smokes white/bluish at stop lights) Smells like pure gas or burned oil out of the exhaust, could it be the rings? not headgasket for sure, since all the cylinders are the same?

Thanks

 

[TSIfreek]

Motors wore out. Good compression tests are in the 150s from cylinder to cylinder

 

[vd96TALON]

Motors wore out. Good compression tests are in the 150s from cylinder to cylinder

I understand, but what do I need to do? Change the motor? My car only has 118k on the clock.

 

[brandonzero0]

Not necessarilly, It might be rings then you'll have some blow by gases passing through the cylinder and rings., cylinder is out of round (needs to be bored) Leaky head gasket, Valves are not properly seating allt he way, timing is off a little is a small possibility but is one. So you CAN repalce it or you can have it rebuilt.

 

[Artago]

Sounds like blown piston rings. I'm assuming those compression results are a dry test. Do a wet and dry test and compare the results. If the compression increases significantly from dry to wet test then you can be fairly certain it's the piston rings.

You don't need to replace the engine but you should have it rebuilt. Get new rings and new head gasket (replace it with something better then stock).

Have the timing checked and replace the timing belt.

You do all that the engine should run much better.

Also, replace the O2 sensor(s) and catalytic converter.

Cheers, Tom.

 

[98mitsuGSX-SD]

Was this a cold compression test or was it done after warm-up?

Numbers will always go down if you didn't allow for the motor to warm up prior to conducting your compression test. If you suspect it to be a leak at the rings, do a leak down test and that will give you some more information as to where your problem is.

 

[Artago]

vd96TALON, do you happen to have the check engine light on?

 

[vd96TALON]

I ran the test after driving for like 20 minutes (because my mechanic is located about 20 min from my home) so I didn't do the test on "cold" car. He told me my pistons rings are worn, and needs replacement, so I guess you're guys are right about the worn rings

My check engine light is not on btw, and also I read that if you're pistons are worn your car would be losing power, and I don't think mine does, it runs straight without any problems. However my timing belt is making a screeching noise, it goes away after awhile when driving but still you can barely hear it..

 

[oldman]

So finally I got them

1 - 115
2 - 112
3 - 110
4 - 110

Seems abit low to me, what do you guys think? (my car smokes white/bluish at stop lights) Smells like pure gas or burned oil out of the exhaust, could it be the rings? not headgasket for sure, since all the cylinders are the same?

Thanks

Was the test done with engine fully warmed up, throttle fully open, all four plugs removed and battery fully charged? Did you double check with a second tester? These are usually the common questions when test results are low but CONSISTENT across the board. If all these conditions were satisfied, the next test would be a leakdown to pin point the problem(s).

 

[Artago]

I ran the test after driving for like 20 minutes (because my mechanic is located about 20 min from my home) so I didn't do the test on "cold" car. He told me my pistons rings are worn, and needs replacement, so I guess you're guys are right about the worn rings

My check engine light is not on btw, and also I read that if you're pistons are worn your car would be losing power, and I don't think mine does, it runs straight without any problems. However my timing belt is making a screeching noise, it goes away after awhile when driving but still you can barely hear it..

Are you sure it's the timing belt and not the alternator belt or some other belt? Timing belts don't screech ( as far as I know ) because they have teeth, and if they slip (or skip should I say) kiss your motor good bye.

Tom.

 

[stocker97tsi]

if it was rings tho, wouldnt it be blowing blue under acceleration too? as the load increased on the motor and pushed more air/fuel past the rings? just a thought..sounds kinda like valve stem seals, but id defenitely check with a leakdown to be sure.

 

[laserspeeddemon]

Yea, thats REALLY low for a N/T. But the smoke you describe illustrates blown pistons rings.

 

[Artago]

if it was rings tho, wouldnt it be blowing blue under acceleration too? as the load increased on the motor and pushed more air/fuel past the rings? just a thought..sounds kinda like valve stem seals, but id defenitely check with a leakdown to be sure.

I had a ESi with blown rings. It only smoked in IDLE after I let off the throttle. Don't know why. It just did. Tom.