I bought a 2003 lancer evolution used about a week ago and am mechanically inclined, the check engine light came on the other day and I took it to a local shop, hooked it up and it gave me a lean and misfire I changed the O2 censors and plugs, went to take it for a test drive and it is falling on it face and stuttering only under boost in every gear. I can hold it to the floor it will stutter for a few seconds and then clear up and go. can anyone help me?

 

Please

 

Mods? Mileage? Condition when bought? Bad tank of gas? What code was it?

 

The guy I got it from put in a ceramic stage three clutch that is very annoying, apexi turbo timer, 3 inch stainless down tube to the cat and stock out the back, full injen piping, front mount ic, and that is about it as far as I know. I pulled the intake tube and the turbo shaft has some side to side play. I used to have a 1g eclipse gsx and it had shaft play but never responded by falling on its face and sputtering. I dont think it is getting enough fuel. Is there a inline fuel filter or only in tank cause the parts house does not list a inline filter. Also i dont know if was tuned after all the work, the mac tool ecm reader says misfire and o2, I replaced both o2's, and the spark plugs they were running very lean. I loosened them with a socket and extention, and the crush rings were not crushed, what kind of dumb *** cant tighten plugs? I think it started screwing up and he got scared and reset the engine light and offed it a quick as possible. I know that if you add an intake and start adding alot more air than a tune is needed, I just want to rule out everything and not waist time paying out the azz for a ton of parts, kind of on a budget after dropping 12gs on my first evo. the turbo timer o a/f mode says 4.27- 4.99 when driving around and the o2 light is also on, if that helps. ALL INPUT IS WELCOME!

 

125,000 miles, prestine condition, only run 92 octane from top companys. no code on the mac tools obd reader. it read misfire and lean on the o2, pre- cat o2 was white from running way to lean and I replaced them both. I have access to every tool and peice of equipment in the shop what shall i do next.

 

well its hard to say if u dont know if ur tuned or not. I would say re-gap ur plugs to .022 and try that out

 

the plugs are gapped to exact spec and I dont know if it was tuned after the obove mentioned mods, cause I did not do them. I have only had the car a week. Please dont waist my time or yours by replying with some bull**** like regapping plugs, I'm no nuub! Ive blown up about 30 4g63 pos motors, and dont ask why i keep buying them, I gots love for dsm

 

mannnn blown up about 30 4g63s....lol some love..what do you do to them..?

 

well, if you know it's lean, check the easy shyte like fuel pressure. no codes means that it's not emissions related. it's gotta be something mechanical. boost leak? air leak upstream of o2? can that crappy mac tools reader take a snapshot? maybe the timings off, maybe the coolant temp sensor is reading off, etc., etc. need more info to help. is the o2 sensor switching high to low volts or just staying high? by the way, what is the o2 light? does your tt have a light? if not, wtf light are you talking about? more info plzzzzzzzzzzzzzzzzzzzzzzzzz.

 

Hey pal, i gapped my plugs at .024 for 2 years, then all of a sudden i had ur exact problem and now have them gapped at .022 with no issues. So go blow up another motor then

 

yeah, he was a little rough on you kid. people get all bent outta shape after askin for help? and blowing 30 motors means you are a noob or you dont learn from your mistakes. good luck.

 

lmao, dont trip bro! I dont believe .002 of gap can effect my motor as bad as it is, thanks for the input, sorry to be a d i ck.

 

yeah my tt has a o2 light, its on.

 

boost leak comes to mind first, bad coil? Or are the coilpack screw holes stripped? Maybe coil is lifting off contact with plug? MAF wire dirty? Just keep adding more info, we'll figure this out.

 

i was thinking that a coil might be going out, I plan on doing a leak test today, I thought the same about the maf and cleaned it, thanks for the input.