Well i just thought i'd throw it out there... i mean you have a turbo timer that obviously ties directly into the car's ignition. what if it has a loose wire or pin? sure, its most likely not going to cause a misfire...... but what if.....

 

The P0300 plagues some people and others like myself haven't had it.
If I were you....I would skip all those flashes and just get a code puller to clear the code yourself. Odds are thats then only thing Mitsu is doing.

If it doesn't affect performance just clear the code and be on your way. I believe the CREADER which can be had for $45 on EBAY automatically removes the code from the ECU and stores it in its own memory. That way you still know you had the code but you aren't driving around with your check engine light on.

 

The Creader is an excellent solution for this p0300 problem. It will reduce your 0300 throws by at least 99% I promise. However I wouldn't consider it a permanent solution, it's more of a band-aid in that it's not _supposed_ to be used in this way. 'Course it could have a two pronged purpose in this world I guess...

nine4surfah, the only issue with the turbo timer/gauge is that your dealer CAN squarely blame them for the misfiring. Wanna know why? Because _THEY_ have no idea why it's misfiring, and Mitsubishi Tech Line has NO idea why it's misfiring, and they will simply default to blaming it on your mods. They blamed mine on my diverter valve.

 

For misfires....I would just for the hell of it replace your plugs and wires.

 

from my experiences with PO3000 codes: dont work on mitsu's @ a ford dealer though
either an ignition problem.
water or sugar in the gas tank.
or even a stuck 02 reading from the 02 sensor causing the entire bank to randomly misfire.
or even a stale bad gas problem. you could try buying gas from another gas station. at our shop we sometimes find buying cheap gas on military bases results in stale gas.

just some of the possibilities.

 

i had the po300 code with a driveablity issue and mitsu kept reflashing it and it never fixed it, so they replaced the tranny(@42000mi) and so far i have not had the code(2000mi). also if you could find someone with an evo with a flash and just borrow that computer to see if it fixes the issue
my dealer had to call mitsu tech support in order to due the tranny replacement

 

RedUSEvo had the same transplant and his returned after 4500 miles or so, iirc.