cocoon

Hi guys, I'm seeking help from those who are more experienced with evos.

I'm going to start from the beginning to when I got my Evo to see if anything I did caused this problem. I got my Evo IV about 2 weeks ago imported from Japan. When I first went to start it it wouldn't start but new spark plugs fixed that issue. After about 10-15 min into my first ride the idle would drop off and the car would stall every time I pushed in the clutch/put the car in neutral (it seemed the idle was set too low and once the car was past its 'warm up idle' it would die out). We bumped up the idle a tiny bit and it was running good. The next day I took it out and took a buddy for a ride and everything was ok. Pulled good and smooth. Once I dropped him back off at home I went to do a pull and the car sputtered/popped and was hesitant on boost. The revs wouldn't climb unless I let off and didn't get into boost. I first thought this was bad fuel but after getting through a few tanks I realized that wasn't the case. We rechecked the spark plugs and realized they were the wrong ones and looked up the right ones and put them in thinking that must be the problem. It wasn't. Same thing once the car warms up and I'm getting into boost a few times it starts to run like crap. It happens every time. We thought the next thing to try would be new coil packs and wires so we pulled the ones off my brothers 5 and it still acted the same. It's only once its warmed up and I've been boosting for a bit. The turbo was apparently just replaced in Japan. The car gives my no codes when this happens.

Any ideas on what it could be and anything I can do to troubleshoot without having to buy replacement parts hoping it will solve the problem?

thanks.

thomasy154

I own a evo 4 and when i started having the same issue and when it started stalling when putting in the clutch and neutral etc it turned out to be crankshaft walk, and needed a rebuild. so i would get that checked out. But now issues under boost suggest maby a boost leak? blow of valve or vacuum. so check that out aswell

ace33joe

iTrader: (2)

Did you fix the problem? Local EVO V does similar and even with new coils/wires/plugs, it still misfires when hot and under boost.

cocoon

Hi, the problem was that my fuel tank had corroded on the inside filling it with rust and debris and also rotting out my fuel pump. When I would start driving everything would be settled to the bottom but as I drove more it would stir up clogging my fuel pump and in turn not getting enough fuel to the engine. To fix it I replaced my fuel pump with a Walbro 255, installed a new fuel filter and cleaned all the crap out of the tank. Hope this helps!

ace33joe

iTrader: (2)

Thanks for your reply!

I don't think it is fuel related for this EVO V as we get enough AFR, but we will replace the fuel filter as a preventive maintenance. (I prefer this replaceable canister type over CT9A's fuel pump assembly type)

michaelanjolo

Having almost exactly the same issue with my Evo IX :/

meka

iTrader: (1)

Are you guys running recirculating or vented blow off valves. Without being tuned for speed density you should be running a recirculating on evo456.
-change fuel filter
-check for boost leaks
-clean maf

when you adjusted the idle how did you do it? biss screw? only adjust that when car is hooked on taxtrix in idle adjustment mode. otherwise you're shooting blind.