four days ago i bought a evo x and not gonna lie, its a bit nicer than my old ix but anyways, i looked in the manual to see how many miles i need to break in the car. so i find out it is 600 and in the few days i had the car ended up with right under that by just driving around after work, so finaly i get on it just to see how the car feels and its pretty nice, nothing crazy but whatever. so today i show my brother the car and now when i go right around 6800ish rpm the car feels like it is missfiring, so i take it to the dealer and the guy says it needs the latest flash so he does the flash and i try it and its fine. so now i just showed the car to a friend and we were kinda getting on it back to back and it wasnt doing it at first but then it started to around the same rpm, he thought fuel cut but i dunno... anyone else have this problem?

 

as many people will point out, the stock Evo X runs super duper rich. Look for a couple stock X dynos and you'll see that the power stumbles off over 6500 or so rpm.

With a tune/flash (that's $600+ and voids your warranty) this gets cleared up.

Also, get your oil changed around 1000-1200 miles and it will help.

 

thats another reason i was told but that just doesnt seem right because i can see it starting to feel slower but the car gets kindof jerky when the rpms get that high, thats why i thought it was plugs but i dunno how a car 4 days old has bad plugs....

 

ill try n get a video of the rpm to show you what its doing

 

i still have the hesitation at high rpms after the reflash. i think if me or you really want to be rid of it, then consider a tune.

it is like a thump/blip,right?

 

honestly it feels exactly like missfiring... It doesn't happen right away but when I get on it a few times back to back it starts to do it, and it's just at the really high rpm

 

what kind of gas are you putting in the car?

I know the quality (or lack thereof) of gas I put in has a very direct impact in how the car feels. 93 + no ethanol = the best performance (to date) for me. However finding it is hard.

When I put crappy 91+ethanol or 93+ethanol in I can really tell since the car seems to hesitate quite a bit more on the top end. Feels sluggish.

 

Heat soak?

 

i put 93+ethonal in the car, i dout it is heat soak.... this used to happen to my brothers supra when he would take it out and run a few people usually after a few runs it would start to missfire and then if you let the car cool down for a couple hours it would be fine again, ended up the coil packs were bad but that doesnt make too much sense since this car has on 600 somthing miles on it now, his car had 110000 miles when that happened.... im gonna try n get a video on my lunch break and post it...

 

what mods are you running on your "X"? Do you still have a warranty? if so, take advantage. this should not be happening on a new car.

 

its stock

 

This problem has been talked to death. You need a professional tune. Mitsubishi is protecting their motors and keeping within standards by running the X rich.

 

ok this is not my car but mine does the exact same thing... does anyone else with a stock car have this problem?

http://videos.streetfire.net/video/E...ter_192168.htm

 

Although the tune is highly suspect, you might also consider checking the plugs if your car was sitting on the lot a long time. I was told by the service manager that they ended up having to replace plugs on some of the 8's/9's on the lot because there were sitting there so long and getting moved around the lot. The plugs got fouled from the car never reaching operating temperature. What's the manufacturer date of your car? Just a thought...I have the latest flash, and my car never stumbles like that.

 

It has been there since April of 08 and I told the guy it was plugs n the service guy said it has to throw a code for him to look at it, the guy basically tOld me to leave, but I told him when my brother had his sti, it blew up twice with no check engine!!!! These people are kindof annoying me cause he won't help me, that just doesn't seem right for a car to act up like that being brand new... I would change the plugs if I had the car for a month or so but I bought it a week ago, they need to fix the car...