C3 LT1 POP POP OUT THE TAIL PIPES

[Phil P.]

i purchased this car recently---with 93k odo---original exhaust--etc---i have the aim on order---all appears stock under the hood---could be some vac. lines in the wrong position (need aim to correct) this car runs good but pops--almost back fires---between gear shifts---cal car with all smog gear intact---i have a feeling when i get the aim and correct the vac lines it might quit the poping---i have noticed other posts about this pop- "backfire" problem wtih this era car---thanks for any---all input

[Robert E.]

Re: C3 LT1 POP POP OUT THE TAIL PIPES

Phil,

Try removing the belt for the AIR pump. I suspect the diverter valve maybe defective. As mine was doing the same as yours last summer, I read a post about the diverter valve dumping to much air into the exhaust. I removed the belt and the popping went away.

I sent the pump and diverter to Bill Hodel for restoration, and it came back as good as new.

Robert
41801

[Duke W.]

Re: C3 LT1 POP POP OUT THE TAIL PIPES

Use a Mighty Vac to pump down the diverter valve, it should hold vacuum. You should also by the applicable service, overhaul, and body manuuals for your car.

Duke