vall38

I'm a new member to these forums and they have already helped me out tremendously, however I was wondering if I could borrow a little more wisdom from some you more knowledgeable members? Ok here goes...

2 months a go I purchased a 03' Evo runs great, bone stock, 36k miles on it.

Last week I'm driving home from work and I'm going about 60 mph on the highway and I feel my engine misfire and it sputters and lags for a min or two and then the "service engine soon" light comes on. Drives fine the rest of the way home after the initial misfire.

I take it to my mechanic and he reads it with his MacTools "Star Tool" and says it was just a "soft code" nothing to worry about, however he says he can't get a custom data stream on it since his tool doesn't read my particular computer in detail. He clears the code out and says if it happens again to come back and he'll do a full inspection.

Fastforward to last night, I get in my car to leave from the office and I notice that when my turbo starts to spool up it jumps about 800-900 rpms and then dips back down to where it normally starts to spool up . So the turbo normally spools up at like 3k rpms, now when it spools it jumps from 3k to about 3900 - 4100 for a split second then it dips back down to about 3200rpms and goes normally from there. It does this in every gear now, no matter how hard or light I press on the gas. My "service engine soon" light is not on and I wondering was my previous misfire and this issue related and what the problem is with my turbo being jumpy.

If anyone has experienced similar problems or can tell me where to start looking for this problem, it would be greatly appreciated.

Warrtalon

iTrader: (6)

Your clutch is slipping - common for used Evos and somehow people never notice until after the purchase. There are probably 850,000 threads giving this same symptom, just fyi.

evozakk

iTrader: (5)

2003 and some 2004 evo's had a problem with misfiring and were reflashed for that. I would check into that. good call on the clutch ^

Warrtalon

iTrader: (6)

Well, no, the P0300 was not a misfire problem - the code would just come up for no reason and references a cyl #3 misfire or something (maybe #4, I forget). I'm sure he has that issue like everyone else, but it wouldn't cause audible misfires/backfires.

CrackerJackToy

iTrader: (24)

P0300, I get it every other day. Its no big deal.

Your clutch is slipping as Warrtalon said, so prepare yourself to buy a new clutch.

vall38

Thank you, everyone, for the useful info.

Now on to more important matters, since everyone seems to think it is my clutch...any pointers as to what I should replace it with?

I plan on adding the full workover of bolt-ons and at some point down the road adding a bigger turbo. So, should I just go for a performance clutch now or get the oem clutch now and wait to replace it with a performance clutch later? Just seems like a waste to replace it twice.

Billy@EnglishRacing

iTrader: (18)

have you checked your plugs?

Warrtalon

iTrader: (6)

Exedy Twin HD cerametallic