I reasently just changed the spark plugs on my evo. Under wide open throtle I get a really loud poping noise that kinda sounds like 2 step. I have no clue what it is. If u guys have any I ideas on what it is let me know

 

What gap did you set on the spark plugs? Not calling you a noob, just checking...

 

How are the AFRs looking when this happens? Has there been a major temperature change between now and when you tunes the car...is your car running the stock tune?

 

It sounds like your spark gap is to big. Check that first, a good start is around 25 to 27.

 

Depends on what mods, what boost level, and what fuel you are running. What is your setup like? You can see the mods in my sig and I just switched mine out with a gap of .022

 

I gapped them to 27. And the car got tuned when it was really hot out and I don't remember what the afr's are off the top of my head I'll have to chec a little later

 

I justt have bacic mods like cams fmic o2 hosing 255 fuel pump stock injectors dyno tuned to 24lbs 10.5 hot side

 

eh, tough to say, but if the problem just started after you replaced the plugs than I would say that narrows it down. Try shortening the gap, with just that little bit of heightened boost levels it might cause a foul.

 

not to be repetitive but i have had the same issues. i guarantee it is the spark plug gap. try closing the gap to .25 (or a little under) that should clear it right up.

and the replacement plugs DO NOT come pre-gapped. if you are still getting break up after you try closing the gap, try getting 1 step colder plugs.

and just wondering what plugs are you using?

 

The plugs are just your basick Ngk copper plugs that are a lttle colder than stock. What plugs do you reccomend?

 

NGK BPR7ES .026 gap...

 

I had this issue when I first got the car, the loud popping sound. I regapped the plugs to .020 and it was fine. I then had to replace my plugs so when I was doing my dyno tune I had a huge misfire, checked the plugs again and they were gapped at .030. I regapped them to .020 and been smooth ever since.

p.s. if you are running colder then stock then you are prolly running BPR8 (I was having p0300 misfires with these plugs). BPR7 work great and should handle up to 400+ hp just fine.

 

I'm wondering WHY YOU CHANGED PLUGS?!?!?
Only time I've ever changed them is when I've had a problem...
Never just woke up and said "I think I'll change my plugs today."

This may help diagnose....

 

Also--- how long have you owned the car?

 

Try lowering your boost if it doesn't break up at low boost then it's your plugs just close the gap to about .22