i recently bought my 91 camaro rs back from this guy and it doesnt run. it has the 3.1l v6.it cranks and almost starts then dies. the guy told me he was sure it was the egr valve. the old egr valve is burnt and melted. i bungied it on and it ran briefly if i didnt let it idle. i put a new egr valve on and now it wont run unless the gas pedal is on the floor. the only thing i didnt replace is the wires and plug that go into the top of the egr valve and all of the insulation is melted away. the motor also smokes white when it runs. could that be the cause of my problems or am i way off. any suggestions

 

Hate to say it but that sounds like a car that has overheated and blown a head gasket,white smoke usually means water getting in the cylinders and a melted egr would be consistent with an overheated engine.

 

Again, I agree with ^. I would also add to check for any vacume leak.

 

turns out it was my exaust leaking at the flange causing the smoke and i cranked it without the exaust hooked up and the motor fired right up. i looked at the catalytic converter and its beat to hell. my guess would be the guy who owned it before me hi-topped on something and hit the cat. then while he was on the freeway a piece broke off and plugged the exaust which caused a buildup of pressure since the car was doing like 60 when it plugged and caused the egr to blow off.
does that sound feasible?

 

while a plugged exhaust will cause an engine to not run right if at all, i highly doubt it will melt an EGR valve, something else wend wrong under that hood, maybe not consistant with the no start condition, but something else. sitting around and trying to figure what happened, wont help, what you need to do is figure out why the EGR valve melted in the first place, it had to be hot as hell to melt something that sits on top of and directs exhaust flow. possibly an internal short, or an overheat, or posibbly a real bad back fire. if the new one does not melt, dont worry about it.

 

thats the plan i just gotta get a new manifold cause the one i got is messed up. then on to drilling out the broken bolts from the block where the manifold sits.

 

ok so i replaced the manifold and bored out the cat. this solved most of my problems but if you push on and of the gas quickly it bogs down the motor and kills it. the only thing that i know of that isnt right is the cat isnt welded i just have it connected with duct tape and zip ties to make sure the exaust can flow all the way through. any suggestions?

 

Mine does that too, and I'm fairly sure its because i need to adjust my throttle position sensor, when i push the pedal it bogs down and then ramps up. maybe give that a shot.