Hi, I bought a b16A and I did a compression test before I installed on the car. It turned out good on all cylinders around 235-210.

Now after swaping, I did a compression test again because I was bored and it came out low compression on cylinder 1... WTH ?

all I did was to spray some carb cleaner on the intake manifold a couple of days ago.

Now cylinder 1 has 90 compression. I added a little of engine oil on that cylinder and it turned up to 240 psi. So I guess my rings are bad.......

Why would this happend?

Shouldn't carb cleaner be like fuel?




Modified by JUN. at 8:37 PM 3/19/2008

 

How long from the time you sprayed carb cleaner to the time you did the compression test?

 

around 2 days ago I sprayed carb cleaner into the manifold but most of it went to cylinder 1. Also my first compression test was around 12 days ago.


Modified by JUN. at 7:57 PM 3/19/2008

 

Dat is weird....you sure you installed the tester right?

 

I did, and I took it out, put it back re-test 2 or 3 times........

the only thing that was out of the engine when I took the compression the first time was the oil dip stick....

 

**** Update

Ok so I added carb cleaner to see if my compression decreased on the other cylinders and it did.... now 2 and 3 has 60 psi and 10 psi compression.... I know that you guys might think that I might be crazy on doing such thing..... But if 1 was bad, then I was going to replace all rings.

But shouldn't carburetor cleaner be safe for pistons ?

I am starting to believe that carb cleaner decreases compression due to the oil residuals or thickness? it makes the rings loose compression ?

Or that my compression tester is bad (full of oil)




Modified by JUN. at 8:39 PM 3/19/2008

 

hopefully, when I get my ecu, Ill start the car and all that cleaner crap will burn.

 

Damn lol Idk dude. My guess is that the carb cleaner cleans off the carbon n **** off the rings...

 

The carb cleaner removes the oil from the cylinder walls, then the oil rings don't seal as well. stop spraying that stuff, you could be doing damage to the cylinder walls.

 

ok but what about the compression rings?

Shouldn't I be getting high compression readings?

 

Help PPL

 

Just drive the car, don't spray carb cleaner.
then do the compression test again. Make sure to open te throttle as you crank.
You cannot have the injectors spray fuel as you do the test, that will skew the results. Disconnect the fuel pump.

 

yea, stop spraying the cleaner until you get it running. i would try a few drops of oil in each spark plug hole, crank it over and try to get some oil pressure back in there. do another test after that maybe