1993 GMC Smoking On Startup

start
engines
gmc
1500

#1

I have a 1993 GMC Sierra 1500 (c/k) with a 4.3 V6 motor with 118000 miles on it. Since I got it with 102000 miles it has smoked on start up. It doesn’t smoke when it runs and it runs really good. But is there anything I can do to fix it?


#2

Step #1 What kind of smoke. White, black or blue. What odor? It could just be water condensation. Is it using a lot of oil?

My guess is it is just condensation so there is nothing to “fix”.


#3

White smoke and I can’t really explain the odor but it sure is smoke, not water condensation. It will use tops a quart in 3000 miles.


#4

if it is a very light smoking like where you have to stand behind the car to see it well then its just condensation. If it is a lot of smoke like so bad that you can hardly see out the back window then it could be a cracked head, if its blue its oil, and if its black its running too rich


#5

Valve stem seals need to be replaced. They let oil drip into cylinders when the car is off. The oil burns off at startup and then you see no more smoke. Cheap fix at a good garage. Requires special tools.