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egui42
08-09-2005, 12:22 AM
Okay, well I know this has been talked about over and over! I just got my first P0300 yesterday on the freeway. Now should I just clear it or get it checked by the dealership? I have the works P2 flash, cams, etc. Can I live with this code b/c I have heard that people have gotten flashed for it and still have gotten it occasionally? Any help would be well appreciated! Thanks

EVO GRIM
08-09-2005, 07:04 AM
I havent got one in 6 months. I think its just the way people drive. If you get on high boost dogging 5th gear you pop a code. Allways happened to me in 5th gear on freeway. At legal speeds of course Tam.

Option2
08-09-2005, 07:40 AM
I havent got one in 6 months. I think its just the way people drive. If you get on high boost dogging 5th gear you pop a code. Allways happened to me in 5th gear on freeway. At legal speeds of course Tam.

Not necessarily.... alot of people get P0300 codes just sitting at idle. I'm one of those examples.

equi42- Did you get the code before or after the cams. I do know that some people get the code after getting cams installed (HKS, WORKS, etc.). Mine started after I got my 269 cams in.

JanSolo
08-09-2005, 08:14 AM
I got my P0300 generally driving in 5th gear at around 3000rpm or so, regardless of throttle position. The problem was exacerbated by runing the AC - timing would get pulled dramatically.

Equi - you might want to check into the Mitsu reflashes for your P0300 issues to see if they resolve them.

egui42
08-09-2005, 08:45 AM
Yes I got them after the cams, I have had the cams in for 7k+ miles and just started using the AC. I was in 5th gear cruising at 3k rpm with the AC on. Im just wondering if I should even bother with getting it flashed.


Thanks for the responses! Keep them coming, please. :wink:

JanSolo
08-09-2005, 09:07 AM
Chrisw had a P0300 error and got the second reflash from San Rafael Mitsu, so he would be a good person to hit up for info regarding it's effectiveness.

chrisw
08-09-2005, 09:23 AM
Okay, well I know this has been talked about over and over! I just got my first P0300 yesterday on the freeway. Now should I just clear it or get it checked by the dealership? I have the works P2 flash, cams, etc. Can I live with this code b/c I have heard that people have gotten flashed for it and still have gotten it occasionally? Any help would be well appreciated! Thanks

I got the p0300 CEL (after a reflash to fix it) only when using Chevron or Mobil gas in a very specific type of weather (like just before a thunderstorm)

I think works has the latest p0300 fix built into their product, but you should check with them first to be sure. If you take the car to the dealer, you might lose the p2 flash, but again Works can verify if that is true.

egui42
08-09-2005, 09:25 AM
Okay, well I know this has been talked about over and over! I just got my first P0300 yesterday on the freeway. Now should I just clear it or get it checked by the dealership? I have the works P2 flash, cams, etc. Can I live with this code b/c I have heard that people have gotten flashed for it and still have gotten it occasionally? Any help would be well appreciated! Thanks

I got the p0300 CEL (after a reflash to fix it) only when using Chevron or Mobil gas in a very specific type of weather (like just before a thunderstorm)

I think works has the latest p0300 fix built into their product, but you should check with them first to be sure. If you take the car to the dealer, you might lose the p2 flash, but again Works can verify if that is true.

Works told me once that I would need to get flashed again after the dealer flashed me. I will have to call Works then, thnaks guys.

Option2
08-09-2005, 09:35 AM
Okay, well I know this has been talked about over and over! I just got my first P0300 yesterday on the freeway. Now should I just clear it or get it checked by the dealership? I have the works P2 flash, cams, etc. Can I live with this code b/c I have heard that people have gotten flashed for it and still have gotten it occasionally? Any help would be well appreciated! Thanks

I got the p0300 CEL (after a reflash to fix it) only when using Chevron or Mobil gas in a very specific type of weather (like just before a thunderstorm)

I think works has the latest p0300 fix built into their product, but you should check with them first to be sure. If you take the car to the dealer, you might lose the p2 flash, but again Works can verify if that is true.

Works told me once that I would need to get flashed again after the dealer flashed me. I will have to call Works then, thnaks guys.

I have the latest Mitsu P0300 fix integrated with my P2. I still get the P0300. :cry:

Option2
08-09-2005, 09:37 AM
equi42-

Did you get valve springs and retainers with your cams? If not, maybe the valve seal contact is being picked up by knock sensor? That's my theory at least since I didn't get the valve springs and retainers.

vtluu
08-09-2005, 09:48 AM
I've been getting P0300 codes a lot too; recently, as often as 3-4 times a week. :shock: Usually just cruising along in 5th gear, though I noticed it will often happen this way: I gun it a bit in 3rd or 4th gear (passing, on-ramp, etc.), then go to 5th gear and settle down into a low 3krpm cruise, and moments later I get the code. At no time do I ever actually feel or hear a misfire (and thanks to having had the Magnecor plug wires for a while, I know what that feels like). And I've never gotten the code at the track (or auto-x) even when my engine was pinging like mad due to riding redline in 108-degree weather.

As far as I know, the "fix" they have is simply to reprogram the ECU to not throw the code so much--i.e. it doesn't actually change the way the engine runs. I have a P1 reflash and custom-tuned fuel maps and getting that reflashed after getting a reflash for the P0300 is more of a hassle than I'm willing to deal with, so I just keep a Palm pilot + OBDII adapter in my center console that I can whip out to reset the code. I've gotten good enough at it that I can even do it while driving. :oops:

egui42
08-09-2005, 12:47 PM
Yes I have spring and retainers, and it was kind of like Tam said. I get it after I gun it and settle in 5th gear. Maybe I will just clear it for now! :cry:

Would the Magnecor Wires have anything to do with it, or spark plugs (are the stock ones platinum)?

egui42
08-09-2005, 12:48 PM
equi42-

Did you get valve springs and retainers with your cams? If not, maybe the valve seal contact is being picked up by knock sensor? That's my theory at least since I didn't get the valve springs and retainers.

That pic scares me!!!

vtluu
08-09-2005, 01:17 PM
Yes I have spring and retainers, and it was kind of like Tam said. I get it after I gun it and settle in 5th gear. Maybe I will just clear it for now! :cry:

Would the Magnecor Wires have anything to do with it, or spark plugs (are the stock ones platinum)?
Stock plugs are iridium NGKs, and I'm running NGK BPR7EIX iridium plugs (NGK's top-of-the-line plugs). Tried running copper plugs as well (BPR7ES); nothing changed.

Oddly enough even though the Magnecor wires caused plenty of misfires at WOT, they never triggered any ECU warning codes. So, I've had real misfires and detonation--none of which ever triggered a CEL. And then I have a ton of CELs for misfires that I don't think really happened. Oh well, so long as the car itself runs fine I don't really care, it's just a stupid warning light.

egui42
08-09-2005, 01:50 PM
Yes I have spring and retainers, and it was kind of like Tam said. I get it after I gun it and settle in 5th gear. Maybe I will just clear it for now! :cry:

Would the Magnecor Wires have anything to do with it, or spark plugs (are the stock ones platinum)?
Stock plugs are iridium NGKs, and I'm running NGK BPR7EIX iridium plugs (NGK's top-of-the-line plugs). Tried running copper plugs as well (BPR7ES); nothing changed.

Oddly enough even though the Magnecor wires caused plenty of misfires at WOT, they never triggered any ECU warning codes. So, I've had real misfires and detonation--none of which ever triggered a CEL. And then I have a ton of CELs for misfires that I don't think really happened. Oh well, so long as the car itself runs fine I don't really care, it's just a stupid warning light.



Here is the run down, well at the shop I work at tried hooking up the OBD II reader and now it says it can't communicate with the car. Could I have blown a fuse for the OBD II port? Can I just disconnect the battery to reset it?

vtluu
08-09-2005, 02:47 PM
Here is the run down, well at the shop I work at tried hooking up the OBD II reader and now it says it can't communicate with the car. Could I have blown a fuse for the OBD II port? Can I just disconnect the battery to reset it?
There are a few different OBDII protocols, are you sure you have a reader that works with Japanese cars?

Yes, disconnecting the battery will clear the light, though I'm not sure if the code itself will clear as well (probably).

egui42
08-09-2005, 03:28 PM
Here is the run down, well at the shop I work at tried hooking up the OBD II reader and now it says it can't communicate with the car. Could I have blown a fuse for the OBD II port? Can I just disconnect the battery to reset it?
There are a few different OBDII protocols, are you sure you have a reader that works with Japanese cars?

Yes, disconnecting the battery will clear the light, though I'm not sure if the code itself will clear as well (probably).

It has worked before, how do you think I knew it was the P0300? Not to sound like a smart ass or anything! I might have to try someone else's reader. 8)

DaveLC2
09-07-2005, 10:12 PM
I usually get my P0300 soon after cold start ups. The idle is a tad choppy but smoothes out after a few moments. I haven't had one in about 1,000 miles or so. I cleared it out with my buddy's deluxe code reader.

Dave

zyounker
09-07-2005, 10:32 PM
I got one on my drive to AZ.. Completly stock ECU... I think it becomes more apparent with the more mods, but it is a problem with stock cars.

Only power mods (if you can call them that) are Greddy Type-S & Drop in K&N.

MitsuMan
09-08-2005, 06:48 PM
Iget it when I'm above 4800 RPM in 4th or 5th usually in 5th at steady throttle for more than about 30 sec and I fell it drop a cylinder its not a fake code but its wierd cause it won't specify which cyl in going out so I can't narrow it down!!!!!!!!!!!!

KazzEvo8
11-09-2005, 12:07 PM
I've had P0300 codes since stock and I'm far from that now. Jon at TRE claims he's made alot of them disappear through rebuilds. Unfortunately, I may find that out w/in the next year or so.

Mine USUALLY occur at about 2800 rpm with light throttle (just maintaining speed) in 5th gear although I've had it happen in 4th at the same rev range and after shifting into 5th and settling into a speed. More apt to happen when the engine is good and warm. New plugs gapped down to 0.024 seemed to help at first but later it was prevalent once more.

Sometimes there seems to be no impact on driveability. Usually the stumble is quite evident and lifting the throttle then hitting it makes it go away. If I can get out of the proximity of 2800 RPM the problem doesn't show up. Unfortunately, in 5th gear, that's about 55/60 so very common on local rural roadways/highways - rather why I drive those sometimes in 4th gear. *eyeroll*

I purchased a CReader II diagnostic device and automatic reset tool. I believe Vishnu is high on these but check with them. They're specific about the right CReader II to purchase. I got mine from e-Bay.

I used a strip of velcro and the screw near the bottom of the dash on the right side of the steering wheel. I removed the screw and punched it through the velcro strip; then screwed it all into place. Dual-sided white sticky foam helps to keep it from rattling or moving and it's always connected.

The system will read the code, display it in it's display logic - usually 3 times - and then clear it. Voila.

I live with it and have about 40,000 miles I believe. I'm about to get another flash for my latest mods. I don't believe it will fix the problem, but hey, a guy can dream, right?

Most folks claim it's a harmonics problem and some kind of vibration sets off the sensor. From what I've read the Mitsu reflashes just "desensitize" the reading. And I've heard very few instances where an owner says it resolved their problem altogether.

I'm not looking forward to the Shepard/TRE/whomever tranny rebuild fix but I need to do something about slow shifting and a vibration at low rpm in 5th gear - which I've also seemingly had since my 2003 was new.

Good luck! YMMV!

chrisw
11-09-2005, 03:47 PM
Mine USUALLY occur at about 2800 rpm with light throttle (just maintaining speed) in 5th gear although I've had it happen in 4th at the same rev range and after shifting into 5th and settling into a speed. More apt to happen when the engine is good and warm. New plugs gapped down to 0.024 seemed to help at first but later it was prevalent once more.


Mine always occurs around the same RPM range. 2200 - 2800, with light throttle, light engine load. the gear selection does not matter.

egui42
11-09-2005, 04:04 PM
Mine turn off after 3 days on its own. Sould I be worried? You think the cpu is recording it?

Option2
11-09-2005, 04:10 PM
Mine turn off after 3 days on its own. Sould I be worried? You think the cpu is recording it?

There is a long running thread on EVOM about this. The CEL typically cycles through 10 starts and then the CEL goes away. Mine just stays on now after I had the latest mitsu fix put on.

egui42
11-09-2005, 06:02 PM
Mine turn off after 3 days on its own. Sould I be worried? You think the cpu is recording it?

There is a long running thread on EVOM about this. The CEL typically cycles through 10 starts and then the CEL goes away. Mine just stays on now after I had the latest mitsu fix put on.

Interesting

KazzEvo8
11-10-2005, 07:43 AM
Mine turn off after 3 days on its own. Sould I be worried? You think the cpu is recording it?

There is a long running thread on EVOM about this. The CEL typically cycles through 10 starts and then the CEL goes away. Mine just stays on now after I had the latest mitsu fix put on.

You have 3 choices to clear the code. HOWEVER, I would encourage ANYONE to VERIFY it's a P0300 before you just assume it is. Also, realize, a VALID P0300 may indicate other issues. No, I don't work for Mitsu, this is just common sense.

The choices are to remove the negative battery cable (resets the world), pull two underhood fuses (just resets the ECU), or use a tool to read and reset the code. Somewhere like a friendly auto parts store (AutoZone for one in my area) will actually use a tool to read it and can reset it if you wish (for free!). I use a CReader II constantly plugged in as described above to automatically reset the code. I do get to see what the actual code is before it resets due to how it's mounted again, as described above.

Option2
11-10-2005, 10:23 AM
Mine turn off after 3 days on its own. Sould I be worried? You think the cpu is recording it?

There is a long running thread on EVOM about this. The CEL typically cycles through 10 starts and then the CEL goes away. Mine just stays on now after I had the latest mitsu fix put on.

You have 3 choices to clear the code. HOWEVER, I would encourage ANYONE to VERIFY it's a P0300 before you just assume it is. Also, realize, a VALID P0300 may indicate other issues. No, I don't work for Mitsu, this is just common sense.

The choices are to remove the negative battery cable (resets the world), pull two underhood fuses (just resets the ECU), or use a tool to read and reset the code. Somewhere like a friendly auto parts store (AutoZone for one in my area) will actually use a tool to read it and can reset it if you wish (for free!). I use a CReader II constantly plugged in as described above to automatically reset the code. I do get to see what the actual code is before it resets due to how it's mounted again, as described above.

I'm pretty sure everyone here understands how to reset a CEL. His question was whether or not the CPU records the CEL. To answer his question....yes it does. I believe the MUT-II scantool can capture the last CEL that was triggered including data such as RPM, throttle position etc at the time the CEL popped.

egui42
11-10-2005, 12:18 PM
Mine turn off after 3 days on its own. Sould I be worried? You think the cpu is recording it?

There is a long running thread on EVOM about this. The CEL typically cycles through 10 starts and then the CEL goes away. Mine just stays on now after I had the latest mitsu fix put on.

You have 3 choices to clear the code. HOWEVER, I would encourage ANYONE to VERIFY it's a P0300 before you just assume it is. Also, realize, a VALID P0300 may indicate other issues. No, I don't work for Mitsu, this is just common sense.

The choices are to remove the negative battery cable (resets the world), pull two underhood fuses (just resets the ECU), or use a tool to read and reset the code. Somewhere like a friendly auto parts store (AutoZone for one in my area) will actually use a tool to read it and can reset it if you wish (for free!). I use a CReader II constantly plugged in as described above to automatically reset the code. I do get to see what the actual code is before it resets due to how it's mounted again, as described above.

I'm pretty sure everyone here understands how to reset a CEL. His question was whether or not the CPU records the CEL. To answer his question....yes it does. I believe the MUT-II scantool can capture the last CEL that was triggered including data such as RPM, throttle position etc at the time the CEL popped.

Thanks, that is what I wanted to know.

MitsuMan
11-10-2005, 07:32 PM
if you wait the code will clear itself