When I'm higher in the rpm range (+5000) and let off the gas I get a small back fire. I do have a small exhaust leak in my pass. side collector just before the O2 sensor. Is this the cause or does it have anything to with the fact I don't have heated O2 wires? And will this harm the engine by burning seals or anything like that?

 

The backfire is being cuased by your leak. It likely isn't hurting anything, but does need to be fixed. It happens because gas loads up in the chambers at the end of the high rpms and then is suddenly kicked out when you let off the throttle. Happens every day to race cars and their engines go 500 hard miles. Then they disassemble them to see what they can trash. Get the leak fixed and it may stop unless you have a really low restriction exhaust.

 

OK ????? when ive been on the highway doing 70mph...and am going into town get down to 45...and i have let off the gas from 70 to 45 when i get back on it that crackling sound coming out of my exhaust isn't just my exhaust your saying i have an exhaust leak..omg i think it sounds badass...when i get off the highway and get on and off the gas only work about 5 times on and off the gas then doesn't do it ne more ..

but it sounds sweet as hell...so your saying i hav ea problem?

 

are you saiying that you like having a backfire?

 

My car backfires all the time if I run it hard. I have not cat or mufflers though. At night the Mustangs see a flame shot out at them from behind my car. Ever watch NASCAR and see them shoot a flame out of the exhaust in the turns when they lett off the gas some? Same thing happening. I just live with the popping when I let off and keep on driving. Mine will probably get better or maybe worse when I install my new LT headers in a few days.

 

Mine is the popping you typicalling here when letting off the gas, it's a true backfire. It's my damn Dynatech slip on collectors. I've been struggling with this leak since I put them on

Larry: how's the bird running thesse day?

 

Yup thats whats causing the pop, the leak. I had the same problem when I put my cat back on. the mid pipe had a leak and caused a nasty backfiring. I couldn't get the exhaust clamp seated there right with out a rattle because of the cross member, so I ended up putting a band clamp in its place.sealed up, no more pop except when Its cold and you rev it, but thats normal for a free flowing exhaust...once it heats up for a few mins its fine.

 

4th of July every day..lol