So I have an 05 Evo and recently it has aqcuired a backfire under load in the middle of a gear. It mostly happens in third but has happened in first and fourth. It does not happen all the time but still does every once in awhile. Has anyone had this problem before or know what it may be?

 

you check your spark plugs?

 

I have not, I replaced the spark plugs and wires a couple thousand miles ago.

 

check them, only 6k miles after I replaced mine with Denso's the gap had some how gotten to big so i had to re gap them....then a while later same thing...so i ended up throwing them out for NGK's a few hundred miles ago.

 

okay i will definitely try that.

 

full exhaust?

 

ya but ive had the full exhaust for awhile now and the backfiring just started one day. It backfired after shifts when i first put it on but never in the middle of a gear under load.

 

Your spark plug gap is prolly too big, take them out and gap them to .21-.23

 

this happens to me to on ngks the gaps were at .21 and some how went up to .26 .27!!!! regapped them and had all my power back. this has been happening since i got my car tuned on e85 back in 07. I check them about every oil change and have to regap them.

 

^ that's weird, damn I hope I don't keep having the issue

I may just get a COP and hope it fixes it.

 

+1 for the spark plugs

 

ya today is the first day ive had to work on the car so ill be checking them today and let everyone know if the gap has changed

 

ya it just started to backfire under load in the middle of a gear.

 

so i just checked the plugs and the gap was all messed up all of them were around .27. regaped them and hopefully itll stop the backfiring under load. thanks for all the help ill keep everyone posted on the subject.

 

yea I bet that was it,
let us know, also what plugs do you have?