Bigger cam+catalytic converter=more smoke from exhaust until warmed up?
 

My car has been smoking more than normal lately, but if it does it it's only when I first start it up in the morning, smokes for about ten minutes then stops. It's like the car is running rich while warming up, smoking, then when it quits running rich the smoke stops. Anyone else had this happen?

It's a HOTcam, ported heads, random tech high flow cat, PCMforless tune.......

I know mine smokes like a bastard on cold mornings. No cam, but I have a gutted cat. Makes sense that a high flow cat and a bigger cam would act the same. I think the smoke is a result of the AIR pump until it shuts off.

I've removed my air pump. This really freaked me out because I thought all the smoke was a blown headgasket, but the guys I know at the mechanic shop ran a few tests and said for sure that I don't. The smoke gets pretty bad sometimes.

If more smoke than usual is normal I'll live with it, just kind of unnerving to look in the rearview and see a plume of smoke at stoplights:eek:

Even without the AIR pump, i'd think its normal. Mine smokes out the street some mornings.

Ok great, that makes me feel better:)

Anyone else?

mine is basically stock, and on cold days when i start her up for the 1st time that day, she'll smoke it up till the moisture evaporates that had condensed in the exhaust.

Mine has a lot more smoke when cold than before. Big ol white cloud forms at the beginning. It wasn't as much before cam. I did notice that my car stopped producing smoke faster than my friends none cammed cars tho while getting warm..

How many miles are on it? It could be the rings. When it warms up they expand enough to seal up, but when it's cold it might burn a little oil.

It's definitely white smoke...... 138k miles.

The guy I know that works at the mechanics shop said that if a car is loading up on fuel then it can produce more white smoke that usual out of the exhaust. He said that he had a car come in with an injector stuck open and it was pouring white smoke out.

I think maybe the tune on the car is programmed to dump a lot of fuel in while the car is warming up to "light off" the catalytic converter. This might be even more so since I have a PCMforless tune, as I'm not sure if it's running richer at idle now.

white smoke sounds like oil, not runnng rich.. Most likely your predefined cold start fuel trim values are on the rich side. When it hits closed loop, it takes over and is ok.

I thought oil was blue or darker colored smoke......

Yeah, it is. I know mine smokes white, and when you stand behind it, you can smell fuel. If it were bluish and smelt like burning oil, than that would be the problem.

blue and dark smoke is most likely running rich.

This might be a good excuse to buy a wideband and get a dyno tune:eek: