I noticed the other day that when I get in VTEC my car is throwing smoke out the back. Car runs just fine if not better than ever, but I'm concerned this may be the begining of something major. It only happens when VTEC engages. Where should I start and whats the worst case scenario? Thanks in advance.

BTW teh car is an AP1 with just over 80k on the clock.

 

running maybe too rich?

 

what color smoke? white? blueish white? black?

white is steam aka water. water getting into your cylinders.

blueish white is oil. oil getting into your cylinders.

black is fuel. car running rich.

 

How much smoke? I've seen small puffs of smoke on almost all S2000's in VTEC.

 

But your rings are probably starting to get tired. Mine blows a pretty good amount of smoke...valve guides are pretty new and I have a tune so I know I'm not running rich. But at 91k miles I'm sure the rings are starting to get a little worn...compression is still within spec though.

 

I have read that the puff might be due to a bit of oily air entering the intake manifold from the PCV line. Not sure what causes it (maybe increased blow-by due to worn rings results in a bit more crank case pressure, that coupled with the negative pressure of the flowing air in the intake manifold at high RPM, and it might pull/push a bit on that line), but that is what i read.

An oil catch can setup should fix the problem. My car does the same thing, but its worse due to having no cat and being turbo'd.

John

 

It's all black. I have no cat either.

 

If you are in Tampa or close stop by the shop. I will have one of our techs go with you for a drive and see what they think it is. Advice is free.

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