i have 89 iroc 305TPI. i have the bosch type III injectors and holly afpr. the car runs great. the problem or issue is when i start the car it revs to 2500rpm and then comes down and idles normally. also, when started cold in the morning i get a large mass of white smoke when it fires up and then it goes away. also smells very heavy exhaust out the tailpipe. are these related? any ideas?
it has a new tps set properly, and new iac, replaced maf and relays (previous maf issue - now fixed). i have no check engine light and no codes stored.
any help is appreciated!

 

Your white smoke is probably oil burning. Small block Chevies are famous for problems with the valve guide seals.

 

Blue smoke is oil, grey/black is fuel, white is either coolant or condensation... what color is it?

 

this is beyond the basics here. it is white/grey smoke. the car does not burn oil. the exhaust smells strongly and a little rich but the smoke is very light colored and it only happens when started cold and jsut that first puff out the tailpipe is smoke. after that it is fine. my question is wondering if this is related to the high rpm rev on a cold start. my main concern is the high rev. and what is causing that.
thanks.

 

Just a white puff after starting it cold that goes away right away just sounds like condensation in the exhaust system, which is really nothing to worry about. As long as your oil looks fine on the dipstick, and the coolant looks ok and the level isn't dropping, I wouldn't worry about that. Its just condensation in the exhaust burning off/blowing out when you start it up.

As for the gassy smell when first started cold - if it goes away after it runs and warms up a bit, I wouldn't worry about that either. EFI engines do run pretty rich when started cold, just like carb'd engines do with the choke closed. They program it to run rich when cold to act like the choke on a carbureted engine. Once the cat warms up, the smell should mostly go away, and it will go away more as the engine warms up and gets to operating temp.

Does it still have the gassy smell at operating temp? Does the car still have the cat/cats?

 

Why don't you check the vacuum line going to the FPR? Just to eliminate the possibility of a bad FPR diaphram leaking fuel up to the plenum.

 

the smell does go away a little when warm but still smells stronger than it should. the smoke does go away, it just concerned me because it was a lot - it would fill the whole parking area and then go away and no more smoke. it does have cats but they are original, i am wondering maybe time to change the cat??? would the o2 sensor affect this?
fpr diaphram is ok.