Got my evo 6 been running abit poor lately , problem I'm havin is its holding back and popping and farting thru exhaust around 3.5 - 4k revs and just won't rev over that , any help is good
Its got walbro fuel pump , air filter , exhaust , decat that's about it really

 

Could be the mass, do you have anyway to log it? Without data its just a guess but it does sound like a load problem

 

Iv got snap on solus which could check with that , when the car sat still it revs round perfect just when you drive it and put it underload it splutters and holds back

 

Vote for maf

 

maf s dont usually give hassle , start with plugs gap them to .70mm if it persists try coilpacks

 

Cheers I'll check that later

 

Change plugs and coils made it a little bit better now revs to about 5-5.5k and holds back and splutters / pops

 

Check Plug Gap, and TPS.

 

Checked the intake filter?
I had one last week that was sucking in the filter on boost.

 

I had a problem like this it was a ground by ecu.