06MREvo

iTrader: (90)

So to make a long story short I bought my 06 MR last year in December and I couldn't be happier. A little over a month ago I install the Buschur/Warrtalon IX Stage 1 Package and had a custom flash done by Al. The car was running great and no problems at all. On saturday i was going back to work on my lunch break and my SES came on. When i got back to work i went back in the service department got a 10mm and disconnected the battery and let it reset. The SES stayed off till last night it popped back on when i was at WOT and the car starting misfiring and bucking. I have a friend that works at advanced so i had him scan it for me today and P0304 Cylinder 4 Misfire came up. We pulled the spark plug in cylinder 4 and it looks just like the one we pulled out of cylinder 2. Honestly i hate taking my car to the dealership, i would rather fix it myself, if i can. From the searching i have done so far all i have found is tons of info on P3000 and not directly P0304. My question is what have you guys done yourself to fix the misfire and turn the SES or what has the dealership done for you to get it fix? Any info on this would be helpful, thanks a lot.

bigfishs

iTrader: (5)

Try PMing Warr or Buschur or AL, see if they have any idea.

06MREvo

iTrader: (90)

Good point, i'll try that out. Worst comes to worst I will end up taking it to the dealership. I work for Mazda right now and used to be Mitsu till the end of Feb. and the owner of my dealership sold Mitsu to a guy that opened a Mitsu dealer about a mile from us. Of couse this happens after i don't work for Mitsu anymore. If i have to take it to the dealer hopefully they won't try and f**k me over cause of my TBE with no cat and MBC. I really don't want to but maybe i'll put all my stock stuff back on and take it down to them, well see what happens. Any info though on the P0304 code and and what you had to do to get it fixed would be awesome. Thanks

06MREvo

iTrader: (90)

29 views and only 1 reply so far...somebody has to have some kind of info on this code...

staatz

iTrader: (12)

what plugs are u running? the stock ones still? maybe u should upgrade to a step colder or such. How much boost are you runnin?

06MREvo

iTrader: (90)

Yup still stock plugs, the NGK Iridiums that were in there when i bought the car with 17 miles on it. I have about 5k miles on my car and i haven't touched the plugs or wires at all yet. I got custom tuned by Al at 21 psi. Do you think i should pick up a set of NGK BPR7ESs?

06MREvo

iTrader: (90)

bump...97 views...

parrothead

iTrader: (2)

I'm not sure if they make a colder plug for the IX's yet. They are different from the VIII. From what I've read in this forum the plugs for the IX are longer.

BOOSTEZ

iTrader: (1)

Wow. Is this the first occurance of a IX getting the P0300 misfire code? I thought that problem was confined to only the 03-04s?

-M

06MREvo

iTrader: (90)

Really, i thought they plugs for the VIIIs and IXs were they same, sh*t. You said from what you have read in this forum the IX plugs are longer, is there anybody else that can back this up? I haven't really looked into spark plugs for my IX yet so i haven't read anything about them being longer then the VIIIs. If you remember a thread that said the plugs were longer could you post if for me please. I was just about to leave to go to Advanced and put in some BPR7ES, but if the plugs are different then i won't, thanks.

06MREvo

iTrader: (90)

Yeah, I thought so too, but that would be my luck. Lets just hope that the P0300 code that im getting is just a bad spark plug or something easy. *crosses fingers*

PDXEvo

iTrader: (4)

I would try changing the spark plugs, just to be safe, and just make sure all your connections are good. If you are getting a lot of bucking, then I would assume you are actually getting mis-fire, which is bad. I wouldnt go to colder plugs, this will only, most likely, make your problem worse. Just stick with the stockies, and make sure they are gapped properly.

Did you adjust your MBC recently to add more boost or anything? Also, you may have got a bad tank of gas. Try filling up again with a different station to see if that helps.

mikesevo8

If this helps, P0304 is the same as a P0300.
For P0300 - Random/multiple...ECU can't determine the cylinder
For P0304 - ECU can narrow it down to #4.

Here is the info from my '03 manual, but it should be similar..

DTC P0304: CYLINDER 4 MISFIRE DETECTED

TECHNICAL DESCRIPTION
• If a misfire occurs while the engine is running, the engine speed changes for an instant.
• The ECM <M/T> or PCM <A/T> checks for such changes in engine speed.
.
DTC SET CONDITIONS
Check Conditions
• Engine speed is between 500 and 7,000 r/min.
• Engine coolant temperature is higher than −10°C (14°F).
• Intake air temperature is higher than −10°C (14°F).
• Barometric pressure is higher than 76 kPa (11 psi).
• Volumetric efficiency is at between 15 and 160 percent.
• Adaptive learning is complete for the vane which generates a crankshaft position signal.
• While the engine is running, excluding gear shifting, deceleration, sudden acceleration/deceleration and A/C compressor switching.
• The throttle deviation is −0.059 volt/10ms to +0.059 volt/10ms.

Judgement Criteria (change in the angular acceleration of the crankshaft is used for misfire detection).
• Misfire has occurred more frequently than allowed during the last 200 revolutions [when the catalyst temperature is higher than 950°C (1,742°F)].
or
• Misfire has occurred in 15 or more of the last 1,000 revolutions (corresponding to 1.5 times the limit of emission standard).
.
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are: )
• Ignition system related part(s) failed.
• Low compression pressure.
• Injector failed.
• ECM failed.

STEP 1. Check the spark plugs.
STEP 2. Check the spark plug cable.
STEP 3. Check the injector.
STEP 4. Check connector at injector for damage.
and so on....

06MREvo

iTrader: (90)

So going to NGK BPR7ES plugs from the NGK stock Iridiums you think might actually make the misfiring/bucking worse? No, i haven't turned the boost up at all on the MBC since Al tuned it, I turned it down 1 or 2 clicks after the tune actually, not whole turns, but clicks. I just swapped plugs from cylinder 4 and 2 to see if maybe the code that came up in cylinder 4 would go to cylinder 2 now and i reset the battery again. I'm about to leave to Advanced now, so on my way there i'll get some gas too. Thanks for the suggests, keep them coming.

mikesevo8 - thanks for that info. I'm going over some of that stuff now, it sucks having to do this on my 4.5 month old car...

06MREvo

iTrader: (90)

So like i said i swapped spark plugs in cylinders 2 and 4. And i filled up my gas tank just increase there was any bad gas in there. The original code that came up was a P0304, Cylinder 4 Misfire, so you would think if the code came up cause the spark plug was bad then if i switched the plug to cylinder 2 then it would follow, correct? Well, no it didn't. Before i went to Advanced I reset the computer again, but on my way there SES came back on and misfiring and bucking again. We scanned it again and P0304, cylinder 4 again. So i don't think the spark plug is bad, i wish there was another evo around here so i could swap wires with them to see if those are bad, so i don't have to go to mitsu and buy another set, just to see if the wires are bad. Well, looks like i will be swapping injectors tomorrow to see if the code follows a bad injector, if there is a bad one. Worst comes to worst i will have to throw the stock exhaust back on and take the MBC off and take it up to Mitsu......if anybody has any other suggests, post them please, thanks.