Problem with Corsa exhaust

[Zyrus]

I have installed the Corsa Power Pulse exhaust system on my 1996 LT4. I think I notice an improvement in power, but I am experiencing burbling, poping and "farting" on deceleration. My installer says this is normal, but I hope that is not true. Has anyone else experienced this and is there a fix?

 

[Ken]

Welcome To The Corvette Action Center Zyrus!

Welcome to our family Zyrus.

Backfiring (or popping) on deceleration (as opposed to acceleration) is generally caused by a lean condition. What happens is that the mixture leans out enough to where is fails to ignite consistently. This in turn allows some unburnt fuel to get into the exhaust pipes. Then when the engine does fire, these unburnt gasses are ignited in the exhaust pipe, causing the backfire. Aftermarket pipes often increase backfiring.

For more information, visit More Details on Carb-Related Backfiring. It's a site for Virago motorcycles, but the article explains the phenomenom well.

 

[Zyrus]

Problem with Corsa

Thanks for the reference, Ken. I need to have the engine checked for proper fuel mixture. From my reading of the material it also appears that it could be a problem with the exhaust header gasket not sealing properly. Thanks again for the quick response.

 

[Skant]

Leaks in the exhaust system... particularly near the engine... will cause backfires. Since that's the part that changed, that's probably where the problem lies.

- Skant

 

[Zyrus]

Leaks in the exhaust system....

Skant, you were right. Lose exhaust header bolts were the culprit. Thanks for your comments.

Zyrus

 

[Skant]

Heh. My old hotrod pickup (which had a vette engine in it) had the same problem at one point, that's why I suggested it.

Check those bolts again in a week. And again in a month. Especially if you just put new headers on it. They have a way of loosening up initially. You gotta keep making sure they're tight until they settle.

- Skant