I can drive my evo through town and on the freeway as long as I don't boost. But the second I boost it spools up and then misfires, and I'm assuming its because its not getting enough fuel. Has anyone experienced this? What can I do to solve this "lean" problem? Could it be a faulty injector? Could it be a faulty Walbro 255? Thanks

 

Could be bad spark plugs.

 

What heat range plugs and what gap?

aaron

 

Are you running a boost gauge? If so what does it get to?

 

Im not sure, their NGK's and they were done at 22,000 miles, the car now has 36,009 miles. I talked to the previous owner and he said that it would do the same thing to him, he said that I'm driving it in-correctly, which makes sense. If im on the freeway in 5th gear at 70mph at 3000-3500rpms, he said the way the car set up that if I put my foot to the floor in that scenario I will lug the turbo and it will feel like I'm miss-firing, he said that I need to be in 3rd-4th gear in that scenario. The rain stopped last night so I took her out and had no problem at all, it drove very nicely. He also told me the way the car is tuned that it has to run lean when I'm boosting because of the 100% methanol tune thats in the car. It just scared me seeing the air/fuel drop so low, Sorry for the false alarm guys...

 

The boost gauge shows a full 30psi, Its tuned at 30.78psi. Sorry for the false alarm. "read above"

 

sounds like u need a new set of plugs gapped properly, and have a couple datalog pulls to rule out if your knocking, or if your drivetrain is giving off phantom knock, which can happen at highway speeds, use mitsulogger or somethin equivalent get that checked then go from there. If you pull the plugs, check coil boots and plug wire boots for cracks, and re lube them before reinstall with dielectric grease, issue still persists at least you ruled out # 1 possible cause then go from there. Are you sure all vacuum lines are connected? fpr? other lines? etc....
good luck

 

Are you currently running the meth kit? Cuz if not and you're running the meth tune yes you'll be running lean, and will need a retune if not...

 

Ok, I will get a new set of plugs and have them gapped properly. What kind do I get and how much do I gap them? The previous owner said that thier particularly gapped to this tune from ER. As of yesterday, I took it out to see if it would shutter under boost again in 2nd gear and it did, so I stopped driving it right away. Thier is now a light consistent tapping in the top back left corner of the engine bay. Some of my buddies said that it could be an small exhaust leak, could be a faulty injector, could be a dirty injector. I just need to take it down to ER for peace of mind, I'm just afraid to drive it down...

 

I am running a meth kit, ya i understand. My buddy scared me to death when he said I was running lean and then I talked to ER and I believe Aaron said that it has to lean with the meth.

 

Lean in the map to make the meth work, but if the meth isnt coming on the car will be lean under boost. When you get a chance to drive it down it will be okay, out of boost lean doesnt hurt it.

aaron

 

map meth

 

i would recommend since your runnin high boost and meth, maybe a one step colder plug like a ngk bpr8es( which is what im runnin now), or if you can swing it step up into a one step colder iridium spark plug( denso iw24 if its an evo 8), if theres a consistent tapping thats not good, it couldnt be an exhaust leak due to the exhaust mani bein in front of the engine not where the intake mani is...tapping is usually valvetrain related, your best bet, to rule that out is get a stethoscope like what the doctors use, and put it on the valve cover starting on intake cam side, and listen for un normal noises. then go from there. your car should be fine just keep your foot at the same position on the gas. As for it not running right put the plugs in first, stay out of boost till u get there as much as you can.