HELP! backfire under load
Thread Starter
Teching In
Joined: Dec 2024
Posts: 32
Likes: 0
From: Pa
HELP! backfire under load when ever i am at low rpm under throttle it will back fire loud like a gunshot i have not missfires is just started happing and i have not changed anything
mods are cam,injecters,ls6 intake,and i did get a good dyno tune a bit ago it looks like im running ritch i am on stock fuel pump tho so not sure i dynoed at 377 im lost with ideas
mods are cam,injecters,ls6 intake,and i did get a good dyno tune a bit ago it looks like im running ritch i am on stock fuel pump tho so not sure i dynoed at 377 im lost with ideas
You need to check your fuel pressure. You are insanely lean almost everywhere. In some spots your closed loop fuel trims are trying to add 60% more fuel. Even with a bad fuel supply, I can't imagine what your tune looks like, for the fuel trims to be so all over the place. Post it up if you don't mind.
Thread Starter
Teching In
Joined: Dec 2024
Posts: 32
Likes: 0
From: Pa
You need to check your fuel pressure. You are insanely lean almost everywhere. In some spots your closed loop fuel trims are trying to add 60% more fuel. Even with a bad fuel supply, I can't imagine what your tune looks like, for the fuel trims to be so all over the place. Post it up if you don't mind.
Have you checked for vacuum leaks? Backfire or sputtering under load instantly makes me think something like intake gaskets... Do you have more than a code reader? I'd plug in a scanner and look at the live data. From MAF, crank, cam etc sensors and all. Just to make sure their parameters aren't in red. Make sure you have proper fuel# also. Might be worth checking plugs to see if any hairline cracks in the porcelain also.
