Car is a 2001 A4 1.8t fwd tip, 85k miles.
I just did a compression test for the first time and these were my results:

cyl 1 - 135
cyl 2 - 130
cyl 3 - 130
cyl 4 - 125

Are these numberslow orabout normal?

I was checking for a blown head gasket (car is smoking white out the exhaust) I don't think the car was completely up to temp before I turned it off and ran the test, but it was smoking really bad.

Also, when running the test the pressure would build something like 45 psi on first stroke, 90 psi on second, then stay at130 psi. Is that normal, or do I haveworn piston rings?

Thanks in advance for any replies [sm=smiley20.gif]

 

Pressure should build like that, but your compression #s are on the extreme low end of the range. A good range is 150-180psi. It is good that they are all within less than 10% of each other. My opinion is to do the compression check over again after the engine has completely warmed up. If the #s are stilllow, try adding a little engine oil (maybe 1/2 oz.) into the cylinder throught the spark plug hole and see if the compression #s improve. If they do improve some, you probably have worn rings/cylinders. If the compression does not improve, the air may be leaking through the valve stem seals, head gasket, etc...

 

^^^^Couldn't have said it better myself.

 

Alright, I got the car up to temp and did the test again, this time the numbers were all about 140. I tried the oil in the cylinders on #1 & 2, and got 160 & 155. So I'm looking at worn rings/cylinder walls. Is it time to rebuild or is this still passable?

Also seems the source of the smoke in my original post is the turbo, it was making a death whine as I was driving the car up to temp. But I stopped the car and looked at the smoke, and it still looks white to me, not blue at all, is there any way coolant could get into the turbo?

 

Try a leakdown test. It will show you where the gasses are going. They are more accurate and more informative than a compression test although you will need the proper gauge and a compressor. B.

 

Is there a DIY to perform the test??

 

The compression check diy is hiding under the A4>>Good Thread Links>> section.
https://www.audiforums.com/m_689390/tm.htm

 

 

hiding is right....very nice write up though. Wish I found it before I did it[:@]