I did a compression test on my audi over the week end and here are the numbers

cylinder #1 130psi
cylinder #2 120psi
cylinder #3 130psi
cylinder #4 120psi

cylinder #1 is closest to the front or the car and cylinder #4 is closest to the firewall. the compresion tester i used only reads in 10psi increments.

are these normal? they seem alittle low, but all are with in 10% of each other.

I wish i would of found the Diy on this sooner these numbers are on a cold engine, i did the test as a spur of the monemt thing since i found my compression tester i wanted to use it,but forgot some of the steps ill do it again and compare the numbers.

 

Turbo'd?

Good N/A engines for hi-performance usually have 180psi or higher of 'cranking' pressure. Over 200psi leads to detonation.

 

it's a turbo ill be warming up the engine and trying it again this weekend or sooner if i get the time

 

Stock numbers should be around 185. Make sure you do it on a warm engine and if the numbers seem low you can put in a tspoon(cap) of oil into the cylinder to see if the compression goes up.

 

So these number thusly mean squat. A proper compression test is performed on a warm engine. Like Mike said.

 

yea pretty much i could not reamber if it need to be a warm or cold engine
we all make errors from time to time

 

Yeah, but you screwed up, BIG TIME, buddy!

No, just kidding. Post the numbers with a warm engine. I bet you'll be happier with the results.

 

well i did it on a warm engine this am and the resukts are:

cylinder #1 190psi
cylinder #2 190psi
cylinder #3 180psi
cylinder #4 190psi

but i also think my compression tester is a pos since i did each cylinder 3 times hitting the presure release on the compression test after each time, and i got 3 different numbers from any were from 180-240psi the numbers above is the lowest i got.

 

what does it mean if the numbers are low and you put a splash of oil in the cylider and it goes up on the compression?

 

i'd go to autozone and borrow their compression tester. you're readings shouldn't differ each time by 10-15psi. one the same cylinder and same tester