Ok hello first off, I am new to the site and hope to learn a lot of information about these cars.

Next I have a 97 Prelude with about 120k on the motor, and I notice a ploom of smoke after being stopped at a stop light for a period of time. Also smoke upon heavy acceleration. I know that under WOT our cars tend to throw out smoke (black which is fuel) but after a stop light it is grey which is oil. Now my first thought to that is valve stem seals for the stop light issues. Can that also cause some smoke during WOT?

Next I did a cold compression test today (unfortunetly my compression tester would not read when I attempted to do a warm test so I think it broke) anyhow every cylinder was at 150psi cold, did not do a cap full of oil due to me wanting to do it when warm.

Is 150psi low for cold? I will get another tester today or tomorrow but I just wanted to see what you guys thought?

 

Sounds a bit low to me, were all of your cylinders within 5-10%, as that is also an important factor.

 

Well the test was done while cold so that does affect it and yes every cylinder was at 150psi, not gaps not even by 1psi

 

might want to get another comp tester.... and yes valve seals could be the problem
does it smoke at start up too?

 

Yes it does for just a bit, than it goes away. It will only smoke on WOT and after being stopped for over like 30 seconds. Since compression even cold was 150 consistently I can safely say it's not a head gasket correct? and it could be the rings are leaking a bit but even if so than i'll do a warm+wet compression test tomorrow.

 

Update, so I did a warm test today and in order from 4 to 1 the compression was, 175,179,179,179
wet test showed 180,182,181,181 which is really not an increase so worn piston rings is out.
with those numbers valve stem seals are probably the case for the smoke correct?

 

If your comp goes up after dumping oil in the cylinders, it means your rings are at risk of your loss of comp.

Frankly speaking, I believe that a rebuild needs to be performed when comp is below 130. Not sure about that but I think thats from the helms. As long as comp is with in 5 to 10 percent of each other and above 130, your are fine.

If you see smoke,well idk, your comp is fine. If you daily it, id leave it alone until its really bad.

 

thanks! I bought valve stem seals so I May as well have them replaced. Thanks for the info