I just rebuilt my engine and i bought the car not running. it replaced the IAC it was F'd up and my car ided at like 1800 rpm. now it idles right but when it is idleing and i give it WOT it will backfire throught the intake. but on the upper rpm's it seems to run ok. any ideas? if i give just a little throttle slowly it seems to be ok. could really use some ideas from you guys. thanks
nick

 

When I rev my engine I also will occasionally get a backfire pop through the intake. No one has ever been able to tell me what it is.

 

mine does it every time

 

Mine will do it consistently for weeks. Then will stop for a while. Weird.

 

i still have the problem guys. any ideas would be great

 

I had that problem before, turns out it was my fuel pump, my pressure would drop below 10 lbs at times, it backfired, was a little harder to start in the mornings, but drove fine, something to check anyway.

 

mine does the same thing if its at idle and I floor it real quick it will pop on the intake side did it stock and does it with moroso cold air and flowmaster.

 

if its the same "popping" that i think your talking about, I dont think Ive ever heard an LT1 that didn't, im not sure what it is, but ive been told that it might have to do with the way the cats were designed... just a thought


Baddboy1705@aol.com

 

turns out it was my fuel pump. i only had like 12psi when it was ideling. guess it was a lean back fire everytime. well thanks for the help guys.

 

[QUOTE=baddboy1705]if its the same "popping" that i think your talking about, I dont think Ive ever heard an LT1 that didn't, im not sure what it is, but ive been told that it might have to do with the way the cats were designed... just a thought


every lt1 ive owned poped when you reved it up pretty high and let off, it would pop about 8 times on the way back down on the exhaust side, this stopped on my first lt1 when I put a cam in it.

this other pop im talking about does it if you are at idle and tap the gas real quick, it will pop the instant you mash the gas on the intake side.