evoterp

iTrader: (3)

I've put 65k on my car, and recently had an ACT clutch installed. After the 4th day of breaking it in, I started throwing the p0300. I've learned to deal with it because I can't seem to fix it (blow off valve has always been recirc..rechecked vacuum lines etc)
The only thing that I am consistent with is that it happens in 5ht gear around the 2500-3500 range ( no boost) I've also noticed this code is likely to pop up after a fill up (within the first 80 miles of the fill up). But I've had it with a quarter of a tank left as well. I agree it has to do with the harmonics that is triggering this. I've got the studdering/hiccuping issue as well and have just accepted it. The only thing I've got left to do is to change the transfer case oil(back to Diaqueen) with the hopes this will at least reduce the vibration, finally putting this p0300 to rest!

TURBevO8

iTrader: (25)

I am just going to buy a code scanner and delete it when it pops up. I mean a year ago this drove me nuts when I owed a lot of money on the car and was basically stock. A year later I almost have it paid off, it is just getting older, and it is at 330whp so I expect to have some minor problems with a modded car. It sucks, but it could be much worse. The code does not hinder performance in any way so that is really all I care about.

Suckface

iTrader: (1)

well to date it has been almost 2000 miles since the input shaft and fifth gear were replaced, several tanks of gas, and plenty of fifth gear highway driving at 3500 rpm's and nothing! again knock on wood!

Jeff_Jeske

iTrader: (66)

If anyone is still having the problem...... you can bandaid it by getting a C-reader off of ebay for $30. This will get rid of the problem. You simply plug it in and forget about it.

TURBevO8

iTrader: (25)

Just an update. I have yet to repeat my last P0300 code that was thrown on May 3rd. Weird. Oh well, at this point I am happy. I bought a code scanner from Amazon just in case I throw any more CELs.

App420

iTrader: (8)

i am having the same issues, but I just had my tranny rebuilt by TRE making me think it isnt the input shaft. I just added a rebuilt tranny, 2.3 stroker motor w/ ported head and new valves and springs, a tilton twin plate clutch, and just started having the same problems... has anyone found a solution for this?

Ph3n1x

iTrader: (12)

The PO300 is practically on every 03 there is. Its not that the car is misfiring, just that the eCU is fooled by some weird noise in the Transfercase IIRC.

Whats happening now is the dealer is trying to fix it, but there is really now way. The things they are doing is just going to make it worse.

Suckface

iTrader: (1)

from my experience to date the following solutions have been tried on my car:

1. Replae spark plugs and wires (running 1 degree cooler plugs than stock)
2. Mitsubishi reflash for the P0300 random misfire code
3. Replaced input shaft and fifth gear in trans. (problem finally solved after this was done)

this problem in my opinion and experience completely resides with a funky haromic coming from the transmission. coupled with an overly sensative cam angle/knock sensor which detects a knock from the vibrations caused by the trans's funky vibrations, not an actual knock, that is why it detects it as random, toe ECU cannot find it in a specific cylinder.......

I have spoken with a couple of people who experience this problem once an upgraded cluch is installed......which from the sounds of your experience maybe what is causing the problem.....

if you have not had Mitsu reflash the ECU I would start there.

edit: as an update, I have put almost 10,000 miles on the car since the inut shaft and fifth gear were preplaced and I have not had a problem since.....

good luck man, I know how ****ty and frustrating that garbage is!

Edit: as an update, I have put nearly 10,000 miles on the car since I had the input shaft and fifth gear replaced.......I haven't had a single reoccurance since, once again I would like to take this time to "knock on wood"

TURBevO8

iTrader: (25)

Well I still havent had my P0300 return and it was been well over a month. Weird.

But I have to say that the dealer fix does work. I mean I used to throw this code every 1 to 2 weeks. Basically the vibration from whatever (TC, tranny, potholes, etc) throws the crank angle sensor off so that the ECU thinks it is picking up knock. The ECU is programmed to only throw a code and cut fuel (the hesitation we feel) when a certain number of counts is picked up. The dealer flash simply sets this count higher and if that higher count is not reached by a certain time, the ECU resets and begins counting again. So the reflash just raises the count from say 30 counts to 300 (no clue how many really but you get the idea). Based on this, it makes sense the flash worked for me and others.

vaboostn33

yea im having the same issue and i was wondering if sum1 might be able to help me out.....i just changed the spark plugs on mine since i thought it was a misfire and there is only 12k miles in the car. when i take off from a launch at about 6g rpm's it starts to feel like a misfire. but wen im already on a roll it rarely happens but still does on occasion. the car is bone stock and is an 05 RS. any1 have ne ideas?

Suckface

iTrader: (1)

this doesn't sound like the p0300 code issue.....the random misfire we are talking about occurs in fourth or fifth gear around 3500 rpms.......when it "detects" the misfire it cuts fuel and retards the time to prevent the knock......what you are describing doesn't match the random misfire issue......imo.........

not to mention that the symptons described above for the p0300 code occur on 03's and some 04's....i have not read anything or anyone who has had the problem with 05's, it was my understanding that mitsu fixed the problem by 05

good luck man, hope you figure it out!

edit: but if you want to try new plugs be my guest, i am running bpr8es's from ngk, I think this is a very popular plug to run in Evo's......

vaboostn33

iv already put in new plugs but the **** still happens. and now it feels like the car isnt performing like it should...like its not running the boost it should but on the gauge it is. i dont get it. can sum1 please tell me wtf is goin on with my car this **** is startin to **** me off. thank you.

TURBevO8

iTrader: (25)

The P0300 code does not hinder performance in any way other than that half second when it studders (if yours even does). It is just an anoyance and nothing more so dont worry. I would get the dealer flash if you are untuned or talk to AMS or Dynoflash and get a mail in flash that includes the P0300 fix and the maps for your mods. If you can live with the anoyance buy a Creader or some type of OBDII scanner and delete the codes when the CEL shows its ugly face.

Suckface

iTrader: (1)

again, what you are describing does nto sound like it is the random misfire issue!

when you changed the plugs, did you gap them?

BOOSTEZ

iTrader: (1)

I have had my car for 3 years now and I have ~44,000 miles. I have had my clutch replaced with ACT, a lightened flywheel, and a custom reflash. I've never experienced this P0300 code (both stock or modded) and I hope I never do because I wouldn't have the patience you guys have...

Good Luck to all!

-M

NOTE: At least I know how where to take it (RRE) if it does poke it's head into my car one day.