Hey All,

A little rundown on the car: 03', 95K, full bolt-ons incl. medium turbo, medium cams, 91 Oct, blah blah.

I am currently chasing a rich AFR condition when the car goes into boost. After a pressure test and fixing some minor leaks and resetting fuel trims, the condition remained. No visual signs of exhaust leakage anywhere. So I said to myself, hell something still isn't sealing right.

I decided to do a compression test with a cheap kit I bought from Amazon years back. It was made by a company called Innova; they make a kit for OHC engines with different adapters and such.

I finally opened the package for first use, lol, and with the car still warm I performed the test and expected the worst. Dry compression across all cylinders was 105 psi! With a planned rebuild @ 120K, I wasn't too disheartened with the results because, despite beating on her- sometimes daily- she had given me trouble free operation since purchase. I didn't bother with a wet test since the numbers were consistent, but started to question the quality of the tool.

So I do a little research about the tool and eventually ended up on the product review page on Amazon. A gentleman left a review stating that using the included extension tube, which didn't have a Schrader valve- skewed your test because you were in fact adding displacement to the cylinder! This resulted in abnormally low compression readings.

After learning this caveat, and thumping myself in the head- I performed the test again, this time without said M14 extension tube, and ended up with 155 psi across the board, lol! Removing the tube netted 50 psi! WTH!

Moral of the story: I have to stop buying cheap tools!
But needless to say, the rich afr condition remains, which will probably lead to a different thread altogether.

Thanks for looking.

 

do you self tune or do you take it to someone?

 

Self tune.

 

That is interesting! I know my compression tester has a schrader valve. I would never have thought of it if there wasn't one.