Hey guys. So its that time of year again for getting the car smogged. For the last 2 years my car smokes on startup, from what i read its probably the valve seals. Before i get it smogged i want to know if i would have to replace my cat because of that.

 

no you dont need to touch the cat. yes smoke is usually from worn valve seals and its a typical thing to happen on thrid gens on startup. i have had an 86 and now have an 84 and 87 trans am and all 3 have done and do smoke on start up. got the 87 last year and it passed smog perfectly even with the smoke issue. so no worries.in case the headers you have listed are not street legal i dont know how strict your states smog laws are but if they do a visual inspection and even catch a glimpse of headers that are not street legal they will fail you right then and there.

 

Glad I don't live on the west coast. All visual in NY, as long as the cat is there no worries.

Just thought I'd add that through my research Felpro seems to be the preferred brand for the valve guide seals.

 

I michigan, no smog, I have no cat.

But My car smokes everytime on start up, 86 tpi 305 only 70k miles, But i know it a very tipicle thing for these cars, so can i just replace my valve seals and it will be good?

 

pretty much. there is something you can buy called no smoke or something like that which may help but yeah your probably going to have to replace valve seals if you dont want any smoke or just deal with it. it does suck when you know your car smokes and someone is sitting in their car next to you with windows down. i hate having to say you might want to roll your windows up, my car smokes... lol

 

Embarassing really... I hear the air chuck is awesome for holding the valves so they don't fall in while you're working. can't wait to not have a cloud every time I leave work.

 

Not to thread hijack or nuthin but more does that too. Apparently 305s like to do this alot, i dunno about 350s. Anyway, what if your car smokes white doing high load and startup conditions. Could it still just be the valve seals or can it be piston rings?

 

i do believe regardless of engine size white smoke on start up tends to usually be valve seals. under heavy load it smoking as well i would think really bad valve seals. i had a 74 nova with a 350 in it and it would smoke some even just idling in traffic and valve seals is what i was told the problem was.

 

everyone mentions valve seals only . a problem that many overlook is sludge build-up in the drain holes in the lower front & rear of the cylinder heads . make sure they are clean/clear . if not oil is slow draining back into crank case = smoke . good luck .

 

never knew that. thanks UNCLE TOM!!

 

it's good to get a response/compliment on a post . some of us who have been around awhile remember old things that are new again . i drove a 54 chev. in 56 when the SBC really came into it's own . i think at 69 yrs. i am the oldest active gearhead on TGO . sorry JamesC !!!!

 

Typically the color of smoke can indicate what is burning.

White=Water/coolant. Could be condensation too.
Blue=Oil
Black=Fuel

How's your coolant level been?