i have a 91 camero and there shouldnt be anything wrong with the exaust, ive also taken it to the chevy dealership for he gas tank recall but they said there was nothing wrong with it, everyone who checks it out says its in good condition.. but sometimes when i start it up (especially after its been sitting out all day or when im at work) it blows out a big white cloud of smoke when its first started, i was just wondering what this is being caused by if anyone knows, and if anyone has had the same problem before, thanks.

 

its usually valve stem seals leaking

 

Is the smoke actually white or is it grey or blue? Each color is somthing different. White is coolant or water in the exhaust. Grey is smoke from too much fuel. Blue is oil burning.

 

it looks white, or a very light grey its not dark at all and it smells like burnt gas or something it smells really bad

 

If it's only at start up and then goes away then it's the valve stem seals.