1990 firebird formula 350 tpi.

its a 85,000 mile car. runs real smooth. drives whit no problems.

on cold start ups, it shoots a puff of smoke. only on cold start ups. i assumed maybe some injector was leaking, but i feel no stumbling problems at all. The car runs as you would expect a 80k mile car to run. How can i find out what the problem is? any ideas or inputs would be appriciated. thx

 

Probably seals are old and letting some oil through.
Bet the guides are fine

 

 

yeah my car is original 93k mile car and the seals let some oil through. it's kinda normal with the SBC engine

 

even tho the car is low milage? and how can i make sure if that is actualy the problem... how can i check this?

 

Your car is still 22yrs old. your valve seals are 22 yrs old, they get brittle and leak a little. How can you check them? Take the valve covers off and replace them.

 

yeah the only way to check them is to pull the valve covers and look at them. They can be changed but it can be fairly complicated if you don't know what your doing. you can really screw it up and then valve seals are the least of your worries

 

may i add, that when its cold its cranks more then normal before starting. when its on running tempature, its cranks right up

 

Do you have a fuel press gauge? What I would do is hook up a fuel pressure gauge and start it. See where it is at. Should be approx 43 psi. @ idle. Rev up a little, should go a little higher. Then shut off. If your pressure bleeds down, you have leaking injector(s) which could cause the puff of smoke, leaking check valve @ your fuel pump which could cause the extended crank, or your fuel pressure regulator may be leaking down which could cause both.


If you need help isolating one from the other, I can explain some basic tests.

 

thx alot.i will stop by harbor freight to pick up a fuel pressure gauge.

 

Pick up a pair of hose clamp pliers too. You'll need them if you decide to do any testing. Your car should have the rubber fuel lines at the end of the fuel rail.

 

Like most have stated..valve stem seals. If it were leaky injectors, the hot starts would be affected too.