ok so i figure ill move the post over here, mayb e someon can help....plug gap is set at .45 , all exhaust is tightened, timing has been advanced from 0 -2-4-6-8-10-12, nothing helps , whole ignition system is new, coil cap dist rotor ignition coil plugs and wires. the backfire only happens on a de-celleration , lets say after i go 60-100 mph on the highway....when i start de-cellerating, itll backfire...liek a shot gun. there are no leaks on any hoses anywhere, ....--every sensor is new as well....i have no power loss at all. any ideas?

 

hey .. try to check the injectors... RUN a fuel system cleaner... ALSO , make sure that the rotor is on in the right spot.. That's all I can think of...
Good Luck

 

by the way... search on ULTIMATE TBI MODS, that'll help , and for intake , Edelbrock makes a performer manifold DESIGNED for TBI, AND EGR... it retails for $219.95

 

Gutted cat?

 

Ya shoulda looked at ur mods lol, my bad i get that every once in a while as well, and I noticed when i had my cat in it didnt do it and now that i have it gutted it does sometimes. Its not a very loud back fire right? I think thats just it.

 

LOUD back fire....like a shot gun

 

Even so a gutted cat can do that.

 

well, it never did it before, and its been gutted for 6 months.....i swear it some stupid hose or the EGR valve dying or some SIMPLE thing that im over looking.....oh well.....if anyone has any ideas, feel free to post em lol.....it sucks winning a race then hearing KAPOW!!!! woohoo, i won but my car is a POS lol...people will start thinking im shooting at them, oh....i forgot, i uplugeged the egr hose line, and drove it for a day, backfiring increased GREATLY, ....so perhaps it is the egr valve just dying....i dunno though, i push the diaphram up, and it pushes air out the nipple fine....who knows, ill replace it for the hell of it just to eliminate that possibility, its only 15 bucks

 

Sorry man donno, check timeing (no spark plug wires mis matched [fireing order] its happened 2 me ) as for the cat thing ya i havent driven mine for like a week and i took it out thats not it i get like a lil clunk when im deaccelerating sometimes from teh cat it doesnt back fire really. Let us know.