bad backfire when in 100% boost

[geno414]

hi i have just got this problem and never had it before it started yesterday .

I can drive the car normal just like any other car the car runs really good and a/f is good i am running around 18psi . I have changed the spark plugs today set the gap to .032 and am running cop set up never had a problem till yesterday . but when i start going WOT i will get multiple back fires like i am running anti-lag or something and will not go i have looked and looked no one really has said how to fix this and i am so stumped can some one tell me what is going on ? how to fix this .

also i am running an adjust fpr at 43.5 psi i have no engine codes , fuel lab filter with 6an lines . please can some one help ?

 

[pur97tsifwd]

Try taking the cop setup off and put the stock setup on and see if that fixes it.

 

[geno414]

that's exactly what i thought about doing i am going to try it in the morning but can more people help out please like a wiseman ?? or snowboarder some one please?

it only backfires when i get into boost hard but if i ease into it it wont backfire but if i just stomp onto it it will sputter and back fire like crazy!

 

[blakmoondsm]

Try bringing the gap down to .025, and see if that helps.

 

[fallout mike]

Sounds an awful lot like fuel cut off to me.

 

[Archer Fabrications]

I'd bring gap down to .020 thats what english set mine at.

 

[geno414]

Try bringing the gap down to .025, and see if that helps.

ok will do should i do that on the cop set up or when i use my stock coil pack ?

Sounds an awful lot like fuel cut off to me.

well i am running RC660cc with a walbro 255hp pump aromotive afpr at 43.5 psi and a hi flow flue filter and 6AN lines going to the fule rail also dynoed for 25psi tho its all tuned and everything it just out of no wear started doing this and i don't know why

 

[fallout mike]

I had one several years ago with your symptoms. Before I got it figured out I had detonation. I scrapped all my mods and started over.

 

[Dsmkauai]

What's your injector duty % on those 660? But sounds like the cop setup could be to blame or fuel cut, but I'm sure if your tuned to 25psi and only running 18 it wouldn't be.

 

[geno414]

What's your injector duty % on those 660? But sounds like the cop setup could be to blame or fuel cut, but I'm sure if your tuned to 25psi and only running 18 it wouldn't be.

to be honest i dont know thats mine is all tuned and stuff i am going to swap the cop for the coil pack tomorrow and i will let you know and the tuner said that my 660cc's are perfect for my set up. it's never done this before just started doing it yesterday to be honest.

also still have stock boost sil hooked up

 

[Dsmkauai]

So when it started yesterday did you notice anything that happen right before or did you change anything. You might have sprung a boost leak!

 

[geno414]

fixed the problem swaped out the coil on plug set up for my stock coil pack and no more backfire i must have a bad coil in the coil on plug some wear going to see if the seller can send me a new set up thanks everyone for the help !

 

[fallout mike]

Glad you got it figured out.