i have been misfiring like a **** on 5th gear around 3k-4krpm. only does it on the freeway. WTF. i have try everything this forum have to offer, from new coils,new cam angle sensor, new sparkpugs. DealerFlash 2 times. it stop misfiring for about 2 days and now it's back. I'm about to sale this evo. Help please.

 

Don't give up yet! What year is your EVO? I am assuming an 03. If this is the case there is a TSB regarding this problem. I do not know the TSB #. Mitsubishi will now REPLACE your transmission if the dealer flash does not work. I just talked w/ Mitsu yesterday regarding this problem. This is one of the reasons I traded in my 2003. Mitsubishi refused to acknowledge the problem previously.

Good luck!!

 

What happens if you turn boost down a click?

 

How do you know it's Misfiring?

 

Interesting. A new tranny huh? I wonder if this applies to '04s. Although I am going to try the reflash first. I know mine is misfiring because when I am going onto the highway from the onramp in 4th gear at half throttle the thing dies for half a second then goes back to normal. It feels like slamming on the breaks for just a sec and then normal again. A little later, the SES and then even a little later Autozone verifies the P0300. Only happened twice though about 1,100 miles apart. Only 15k miles on the car too w/ just a tbe. Hopefully the flash does the trick w/ my '04.

 

Welcome to the world of P0300!

There is no fix... other than having the tranny rebuilt.

It all stems around a harmonic resonance through the tranny, triggering the knock sensor.

There is a band-aid though. Get a "creader" from Ebay, and leave it plugged in all the time. It defeats the P0300 cycle.

 

So you think even in my case where it seems to actually be misfiring it is just the harmonics from the tranny throwing off the sensor? How common is this P0300 problem? Like what percentage of owners would you say throw this code?

 

I've seen the code a few times.. been over a year since... I never had any type of misfire that I would notice.. just the code.. but that's a whole different discussion.

It only does it in 5th gear?

 

Yes, it's harmonics triggering the knock sensor.

All early '03 models have it.

I almost never see it in '04 or newer, unless it REALLY is a misfire problem.

Get the a creader.

 

I am curious if vboy425 is positive he had the correct flash from the dealer. Arent there a few different versions? I read the TSB from Mitsu on this and there are certain codes for 04s and 03s and maybe some dealers arent responsible enough to use the right one? It's possible I guess. I just hope the new flash works so when I get tuned I won't have to worry about warranty stuff like this.

 

Fifth gear around 3.5k-4k and accelerating.No reflash from Mitsubishi yet.I just use my creader and move on down the road.

 

Does the Creader erase only the P0300 or ANY other code that may show up?

 

Well like I said, I believe in my case it actually is a misfire. Two times I had the situation described above and two times I threw a P0300. Weird thing is it was few days later and not right after. It's under warranty so I'm gonna take it in and have it looked over and get the new flash just incase. I mean, hey, why not? It's free.

 

If I throw a code after Al's tune, then on to the creader.

 

thanks for the replies everyone i have ordered a CREADER hopefully this will fix it. Anyway it's a misfire forsure, i have my pocketlogger. I'm pretty sure it is. always pull p0300. I'm a tuner myself. I don't feels like spending $1300 bucks for AEM EMS. Also my evo is an 04. Like everyone said i'm pretty sure it's the freaking tranny vibration. I have a 6 pucks clutch.