Most likely bad valve guides and seals. Pretty normal for a high mileage Chevy.
my 1958 Chevy will not start sometimes
Need more info such as the year, engine size and what color smoke.
If you notice it when you first start the engine, it could be bad valve seals and/or loose guides.
That is fine. Its just the hot exhaust meeting the cold air. When it smokes on warm days on start up, then there is a problem, and if it does that then its probably the injectors going bad.
check your fuel pressure.
if it smokes when you first start it, or sometimes if it has a tic tic in the top end intill it warms up
car sometimes will not start up right
Try adding more gas
If your 6.5 Chevy diesel smokes white smoke when you first start it up, it could just need warming up. It could also indicate an issue with the motor.
Spark plugs, wires or timing off
what can make car sometimes have trouble starting then sometimes start right up and then sometimes drive good down the road and sometimes cut out please help
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