When I crank my 94 S10 Blazer SLT Tahoe, there is a puff of bluish white smoke. That is the only smoke that comes out from the tailpipe. Just recently replaced the oil cooler line and changed the oil and filter. It did this before then also.

Just wondering what it could be. It doesn't smoke at all except for when I first crank it and it blows out that puff of smoke. Thanks.

 

its just old valve seals leaking a little oil into the cylinder(s). Typical for the older 4.3 and wont harm anything. Just check oil once in a while and you are set.

 

pretty much every old chevy i own does this. i put some lucas additive in it every other oil change and it seemed to knock the smoke down a bit

 

Thanks guys. I may get around to changing the seals one day, but no need right now. The main problem I had with oil leaking was the oil cooler line which had been replaced and took care of the oil leak. Was going to change the oil pan gasket but was told to leave it alone if it wasn't leaking. Thanks for answering my question.