PO300 code, car undriveable, need advice

super97gst · 04-20-2008, 02:19 PM

I have been dealing with this problem now for a little over 2 months. We have had a thread going on this same thing as well for a while, but i still can't figure out what has gone wrong on my gst. It also hasn't been driveably since this all happened. 2 months ago when all this started i was sitting in the car with it idling. I was messing around with the BC and as soon as i put the car in reverse and started backing up the bottom fell out of it. It's kind of hard to explain the symptoms. The car now idles at 100 rpm's or less, but it will stay running, it will not die while idling or any other time. The engine also shakes horribly bad, like i've got 1 or 2 dead cylinders. After this happened i just shut the car back off. The next day i went back out and cranked it up and it was just fine. I drove it for 3 days with no problems at all. Then i was about 15 miles from home and cruising down the road and it started again. I barely made it back home. The car took forever to get to 60 mph. It will only rev up to about 3k, and it's really slow about getting to that. Also the boost will only go up to 5-6 psi.

I ran a diagnostic check on the car and it threw a PO300B code. It also gave me a PO141B and a P1104 code. The 141 code says 02 sensor bank 1 - S2- Htr. malfunction. I assumed this was from eliminating the cat with my downpipe. The 1104 is a manufacturer controlled fuel/air metering. I looked that one up though and it said turbocharger wastegate solenoid malfunction.

I dont know if that could cause the PO300 or not. Also, the scanner said this too. Fuel system Status - Bank 1 - OPDC, Bank 2 - Disabled. I dont know if that has anything to do with this problem either.

These are the things i have done so far, and these were all brand new oem mitsubishi parts. CAS, ignition coil pack, NGK BPR6ES plugs, NGK plug wires, coolant temp. sensor and i was told an alternator could cause this so i put a new alternator on as well. I have also tested the IAC motor and TPS, both were good. I just pulled the battery out of the car to make sure i hadn't broken any wires or ground anything accidentally, couldn't find anything. What do i do next guys, i really need this car back going. 2 months is a long time to just have the thing sitting here doing nothing. I'm open to any and all suggestions if it will just get it fixed. thanks a lot.

Blake

Rob10_99 · 04-20-2008, 02:29 PM

So on cold start it runs fine, but when its warm it idles low?
Do you have any surging idle?
Have you done a boost leak test? I don't know what BC means sorry,

Its good that you got some new parts, I can't believe you bought a new OEM CAS sheesh!

For your OEM boost controller malfunction, is the bcs hooked up electrically and the wastegate hose?

super97gst · 04-20-2008, 04:51 PM

Quote:

Originally Posted by Rob10_99

So on cold start it runs fine, but when its warm it idles low?
Do you have any surging idle?
Have you done a boost leak test? I don't know what BC means sorry,

Its good that you got some new parts, I can't believe you bought a new OEM CAS sheesh!

For your OEM boost controller malfunction, is the bcs hooked up electrically and the wastegate hose?

No, i never said anything about ambient air temperature making any difference. since the last time this happened 2 months ago the car runs on 2 cylinders at all times. And no, no idle surge. Boost leak test was done in the first run of diagnosis. BC means boost controller. The CAS really wasn't anywhere near as high as i thought it would be. it was 65 bucks, i also bought a new CPS and knock sensor. they were all under 80 each. I just haven't installed the CPS and knock sensor yet.

bboyalan · 04-20-2008, 08:28 PM

Hey Blake! [I finally know your name now haha]

First of all, thanks for posting and sharing in my thread. It's so crazy how you've described your situation - the 100 rpm bogging, 3k, 5-6psi, 2-3 cylinders - all the same EXACT symptoms I was going through! We've replaced pretty much the same parts, except I actually had some wire damage. That's my only suggestion; to check out the wires underneath the battery. Just as another member had posted [voodoogsx], the wires rubbed into the battery mount long enough to cut and touch.

I was reading one of your other threads about holding boost. It made me wonder if a bad turbo with extreme shaft play could be causing my current problem w/ the 3k+ acceleration and tugging/choking.

super97gst · 04-21-2008, 05:35 AM

i went back to some old threads and looked up what voodoogsx was talking about on his po300. he ended up having a wire rubbed down and grounded itself underneath the battery on the main harness. that is the exact thing i did yesterday. i pulled the battery out and i looked and felt of every damn wire in there, nothing. what made me think it could be a wire grounding out there is right before all this happened i took the battery out. and i put a new fuel filter on and replaced the fuel line from the fuel filter up to the fuel rail with SS braided -6an line. but i couldn't find anything anywhere.

bboyalan, did the ecu swap help your situation at all?? i've just gotta find something else that can cause this that i can check.

also, just thought i would mention, when this po300 started it was intermittent. My air/fuel ratio is running really lean, dont really know why though. it only started doing this after i got the po300. i'm to the point i dont really care if i've got a serious internal problem, i just want to know what the actual cause of this problem is so i can fix it. I just called the local mechanic and i'm gonna try to get my car to his shop in the next couple days, so maybe he'll be able to figure something out on it.

Artago · 04-21-2008, 08:59 AM

Hey. Just to throw in my 2 cents. The ECU swap did not help me P0300. But after I swapped the ECU I got a new error P1105 (Fuel Pressure Solenoid malfunction). My car is also running lean so it makes me think it could be a fuel issue. Anyways, new FP solenoid is on the way. When I install it I'll let you all know what effect it had.

Tom

srumel · 04-21-2008, 09:26 AM

Have you checked vacuum connections to the Fuel Pressure Regulator? This could be a cause of some of your symptoms.

Also, the PTM (Power Transistor Module/Unit). Failure of this could cause the engine to run on two cylinders. The method of testing this is in the Hayne's manual.

The only thing that I can think of that would cause all of the aforementioned symptoms would be a stuck EGR valve. This would explain the poor idle quality and inability to build significant boost pressure.

If all else fails, try eliminating your boost controller. Just run a hose straight from the compressor outlet nipple to the wastegate. You could just have a massive boost leak somewhere in that area of the system.

super97gst · 04-21-2008, 11:24 AM

Quote:

Originally Posted by srumel

Have you checked vacuum connections to the Fuel Pressure Regulator? This could be a cause of some of your symptoms.

Also, the PTM (Power Transistor Module/Unit). Failure of this could cause the engine to run on two cylinders. The method of testing this is in the Hayne's manual.

The only thing that I can think of that would cause all of the aforementioned symptoms would be a stuck EGR valve. This would explain the poor idle quality and inability to build significant boost pressure.

If all else fails, try eliminating your boost controller. Just run a hose straight from the compressor outlet nipple to the wastegate. You could just have a massive boost leak somewhere in that area of the system.

all vaccuum connections and transistor are good, already checked. i was wondering if the egr system could cause any of this. i haven't checked any of it though. how do i check the egr valve?? remember that my problem was at first intermittent, so it couldn't be a vaccuum hose popped off or anything. i also had already thought about just eliminating the boost controller to see if it might be a problem there. i will check that tonight. thanks for posting.

Tom, i was wondering about that on the ecu. i thought the way you and bboyalan talked it hadn't made much of a difference. also, i had thought about maybe some type of a mechanical fuel problem causing this. is it possible the pump of regulator could go down, or at least partially go out and the car still run?? however extremely shitty?? i tested all of the injectors yesterday, they all tested 3.2- 3.5 ohms, so the problem is not there.

bboyalan · 04-21-2008, 03:58 PM

Hey Blake!

Yes!! The ECU for my situation in particular DID help tremendously. PRIOR to the swap, my car would barely idle at 600 for its highest and still had the terrible timing that showed in a low, low, low shift point of 1500. Also, I haven't had a CEL for 1 week and 3 days. I want to check my EGR system as well, so if anyone could chime in on this that would be great!

super97gst · 04-21-2008, 06:27 PM

maybe i do need an ecu. with the exception of just swapping it out, is there any way to test the ecu to find out if it's functioning properly??

srumel · 04-21-2008, 07:51 PM

It is possible that the valve was slowly binding due to carbon build up, eventually causing it to fail in the open position. This is only a theory though.

There's probably a write-up on how to check the EGR, but this is my method.

This is for a 1g, but I'm sure it's comparable. I'm pretty sure that the manifold pressure sensor on a 2g plays a part in the EGR operation, so I can't help in that regard, but I think that the mechanics are pretty much the same.
First, locate the vacuum hose that the top nipple on the EGR valve is attached to. Then apply vacuum to that hose with the car running. If the engine's idle drops signifcantly or stalls then the EGR is working properly.

Just to be absolutely sure that the valve isn't stuck you can remove it from the intake manifold and clean it thoroughly with break cleaner and test its operation by again applying vacuum to that top nipple. Reinstall with a new gasket or RTV and torque to spec.

Archametes · 04-21-2008, 08:28 PM

Ok just out of curiosity (and I don't know for sure because I haven't changed mine yet but...) did you put the Fuel filter in the right direction? I've heard on some of them they are directional and the fuel will only flow at the correct rate in one direction and be seriously restricted in the opposite direction. I know it may sound stupid but if all this started after you changed it , I'd at least double check....

super97gst · 04-21-2008, 08:44 PM

Quote:

Originally Posted by Archametes

Ok just out of curiosity (and I don't know for sure because I haven't changed mine yet but...) did you put the Fuel filter in the right direction? I've heard on some of them they are directional and the fuel will only flow at the correct rate in one direction and be seriously restricted in the opposite direction. I know it may sound stupid but if all this started after you changed it , I'd at least double check....

The car threw the po300 code approximately 3 weeks after the fuel filter/ SS -6 AN fuel feed line install. That has nothing to do with this po300 problem, that's one thing i'm actually sure of. I mean no offense, and you'll see what I'm talking about when you change yours, anyone that knows anything at all about mechanic's work is a complete dumb ass if they put the fuel filter on a 2G on upside down. Like I said you will see what I mean when you change yours. Now on my chevrolet truck, it's very easy to put it on backwards. Both ends look identical. Thanks for the post though, I appreciate everyone's input. Didn't I just post on a thread of yours about kind of the same problem??

As for the EGR valve test, I would be better off taking it off the IM. Since the car has a really hard time running, plus it's running extremely lean. I will just take it off the car and test it. I will post back results tomorrow if I can get it done then.

super97gst · 04-22-2008, 05:49 PM

Does anyone know how to get the EGR valve off the car?? I need to pull it to be able to check whether the valve is stuck open from carbon deposits or not.

lauj2gdsm · 04-22-2008, 06:03 PM

I have the same symptoms you guys.. i have change just about everything. coils packs, injectors, iac, ecu, wires, plug, tps and alternator, check valve springs, timming and still no cigar. let me know if ya find the fix.

Artago · 04-22-2008, 07:12 PM

Next thing on my list is Fuel Pressure Solenoid (I have a P1105 code) and then EGR block off. I'll post back if I get any results.

super97gst · 04-23-2008, 04:50 AM

Quote:

Originally Posted by Artago

Next thing on my list is Fuel Pressure Solenoid (I have a P1105 code) and then EGR block off. I'll post back if I get any results.

I was thinking the same thing. I think I'm gonna just go over Taboo's diagram and eliminate all the emissions. If the EGR is causing some of this I can just eliminate it all. I'm gonna try to take my boost controller off and put it back to stock today if i get a chance. This started while I was messing with my boost controller so maybe it has something to do with it. doubtful though, I'll post back with results.

super97gst · 04-23-2008, 03:23 PM

Ok, I now know why I am getting at least one of the codes. The p1104, which is the turbocharger wastegate solenoid. Apparently when I installed my Greddy boost controller I for some odd reason took the BCS off the car.

. I absolutely would have sworn that I left it there and plugged in. Anyways, I'm sure that's the reason that code is being thrown. I was going to bypass the boost controller this afternoon and see if that was possibly causing this problem. I guess I'm gonna have to get a BCS and put it on the car before I can fix this code. Does anybody know a way to test the boost control valve for a Greddy boost controller??

bboyalan · 04-25-2008, 10:54 AM

What's the update on your situation? Also, I was thinking about your boost controller situation. Since you're not sure if your EBC is functioning properly and you don't have your BCS, have you considered momentarily connecting the wastegate's hose straight to the housing?

super97gst · 04-25-2008, 04:26 PM

Quote:

Originally Posted by bboyalan

What's the update on your situation? Also, I was thinking about your boost controller situation. Since you're not sure if your EBC is functioning properly and you don't have your BCS, have you considered momentarily connecting the wastegate's hose straight to the housing?

Well, no I haven't considered that. Would that work though?? I've got a 97 ECU and BCS on the way right now. Should have it all here and in the car by middle of next week. Like Tom and I were talking about on your thread, I noticed this when the PO300 first showed up. For example, I went out and cranked the car today and sat in it for maybe, 2-3 minutes. When I shut it off and went up to look at something on the engine the exhaust manifold was red hot. Nothing else was, just the exh. mani. I already knew I was running extremely lean, my a/f guage tells me that. I just don't know what is causing it. Also, and I have no idea if this has anything to do with it, but before I the car started running like shit and the PO300 came up I was having some weird cooling issues. When driving at cruising speeds the water temps were normal. But when I would come to a stop or a slow roll the temps would plummet. I just assumed I had a thermostat stuck open, but before I could get it swapped out all this happened. Like I said, I have no idea if that has anything to do with this PO300 or not. What do you think?? I wonder if it's possible the fuel pump could start could be going out, but still pumping a little. That would make it run lean. It's something that's not letting the engine get enough fuel. I just don't know what that something is.

bboyalan · 04-25-2008, 10:02 PM

I remember prior to this whole conundrum, it was taking forever for my temperature gauge to rise towards the center, and even then, it wouldn't be exactly at center point. It turns out we simply had to replace my water housing sensor. According to my dad, it was affecting the efficiency of the car in terms of power and gas. With the old one, the car would be dumping more fuel in order to "heat up" the car. Just a thought

super97gst · 04-26-2008, 05:39 AM

Quote:

Originally Posted by bboyalan

I remember prior to this whole conundrum, it was taking forever for my temperature gauge to rise towards the center, and even then, it wouldn't be exactly at center point. It turns out we simply had to replace my water housing sensor. According to my dad, it was affecting the efficiency of the car in terms of power and gas. With the old one, the car would be dumping more fuel in order to "heat up" the car. Just a thought

You're talking about the ECT sensor? I swapped it out when all this first started thinking that might be the cause. It didn't help anything, but it's possible that was what was causing the temps to fluctuate the way they were. I'll just have to get this ecu and put it on there and see what that does. I also checked my elbow directly above the smic yesterday. Its in good shape, no leaks at all. I also can't find any leaky hoses around the EGR valve. Maybe my problem is all contained in the ecu, or at least something that's causing the engine to not get enough fuel.

I've been needing to install my fuel pump anyways, (Walbro 255). After I get the ecu on the car I guess I'll do that, but I don't think that has anything to do with this. Hopefully the ecu will clear it up.

Artago · 04-26-2008, 11:25 AM

Have you checked or swapped out the injectors? It occurred to me that I haven't heard of anyone trying that. Does anyone have a spare set of injectors we can try?

The reason I'm saying this is that I don't know why we're all misfiring but I know one thing for sure. I'm running rich. So it could be a fuel delivery problem and not an ignition problem. I can't wait for me to get my new fuel pressure solenoid to get here so I can swap mine out.

Tom

bboyalan · 04-26-2008, 12:21 PM

He did mention testing his injectors' resistance with passing results. It could possibly be that there's a deeper damage, but then again, I'm now biased on it being that if not his ecu. I doubt it though because the only "fiddling" done was his EBC install before the madness started.

Blake, have you pulled out your plugs recently? How do they look?

super97gst · 04-26-2008, 08:13 PM

Quote:

Originally Posted by bboyalan

He did mention testing his injectors' resistance with passing results. It could possibly be that there's a deeper damage, but then again, I'm now biased on it being that if not his ecu. I doubt it though because the only "fiddling" done was his EBC install before the madness started.

Blake, have you pulled out your plugs recently? How do they look?

Yes, I did test the injectors. They all passed with flying colors. I was actually hoping one of them would fail the test.

I replaced the plugs with BPR6ES plugs a week or so after I got the PO300. Just like we discussed in your thread, 2 of mine were affected. One was a lot worse than the other though. Both had a lot of gunk built up on them though, they actually looked like they were fouling. But I don't understand how that could be since I'm running extremely lean. The only thing I know of that could cause the running lean situation is either the ecu or possibly the mas. I found an ECU, BCS and a good MAS today. I'll get some money sent to the guy monday, so we'll see if it's one of those parts. I'm planning on swapping out the ecu then checking to see if that fixes it. Then do the MAS, so that I know which piece fixes it, if either do. That way I can post that on here for others with this same problem in the future. I really don't think there's any type of deep damage, like internal damage for example just for the very fact that when all this started the car wouldn't run right, then the next day it was fine for a few days. If I had some type of mechanical damage to something it wouldn't be intermittent. The only thing really that could do that in my situation, just like yours, would be electrical in nature. I don't know though, just like the 3 of us have been doing from the beginning, we're fishing in the dark. All I can do is just wait for parts.

Btw, Tom, what's taking that fuel pressure solenoid so long to get to you?? Does it always take this long to get parts to you in Canada?? Just seems like it's really taking forever.

Artago · 04-26-2008, 10:44 PM

Quote:

Originally Posted by super97gst

Yes, I did test the injectors. They all passed with flying colors. I was actually hoping one of them would fail the test.

I replaced the plugs with BPR6ES plugs a week or so after I got the PO300. Just like we discussed in your thread, 2 of mine were affected. One was a lot worse than the other though. Both had a lot of gunk built up on them though, they actually looked like they were fouling. But I don't understand how that could be since I'm running extremely lean. The only thing I know of that could cause the running lean situation is either the ecu or possibly the mas. I found an ECU, BCS and a good MAS today. I'll get some money sent to the guy monday, so we'll see if it's one of those parts. I'm planning on swapping out the ecu then checking to see if that fixes it. Then do the MAS, so that I know which piece fixes it, if either do. That way I can post that on here for others with this same problem in the future. I really don't think there's any type of deep damage, like internal damage for example just for the very fact that when all this started the car wouldn't run right, then the next day it was fine for a few days. If I had some type of mechanical damage to something it wouldn't be intermittent. The only thing really that could do that in my situation, just like yours, would be electrical in nature. I don't know though, just like the 3 of us have been doing from the beginning, we're fishing in the dark. All I can do is just wait for parts.

Btw, Tom, what's taking that fuel pressure solenoid so long to get to you?? Does it always take this long to get parts to you in Canada?? Just seems like it's really taking forever.

I know what you mean by the plugs fouling being perplexing. Plugs say the car is running rich but the high temps say the car is running lean. Can it be both? And no, not at the same time

. Is it possible that the car is running rich sometimes and lean other times? Just a thought.

Regarding fuel pressure solenoid. Although it is true that parts take longer to get up here in Canada (usually 2-4 days longer) but this time it's just JNZtuning being slow. My order was not processed right away because of some problem they have with their web site and then (after they processed it) they told me that they wont be getting the part until Tuesday the 22nd. So I emailed JNZ and the said that it went out on the 22nd but they can't give me a tracking number because USPS doesn't supply them the tracking numbers (total BS cause MAPerformance just mailed me a Mishimoto Rad via USPS and they gave the tracking number right away... I installed the rad + slim fan today... it's nice

). So anyways, I don't know when the solenoid will get here but I'm expecting it early this week.

On another note. Have you tested your EGR system? That's next on my list (after I fix ALL the vac/boost leaks)

Tom

super97gst · 04-28-2008, 06:51 PM

My EGR solenoid is good, as well as the EGR valve. I couldn't find any problems there. After all this is over and I've got the car back up and running I'm gonna do a total emissions elimination though. On the plug deal, I know the car is running extremely lean, but I don't know what the deal is with the plugs looking like they're fouled. I'm not so sure the MAS doesn't have something to do with our problems.

Is that new rad you bought polished?? I bet that is one sweet rig, what about the fans. Are they Spal slim line fans? Oh, and about the USPS sending out tracking #'s, that's total BS. At the car audio shop I used to work at every time I sent something out I had to get tracking #'s given to me from USPS.

. I talked to the guy that's sending me some parts today. I'm getting the ecu, bcs and mas for 170$. I should have it by the end of this week or beginning of next. Hopefully one or the other is the problem.

Artago · 05-07-2008, 12:10 PM

Hey all. It's been a few days so I decided to post an update. I removed and cleaned the EGR valve. It works fine. No help with the P0300.

I FINALLY got my FPR solenoid. Installed it, threw a P0300 the next day. Oh well... At least it got rid of the P1105 code.

I think I'm going to attack this problem from a different angle. Instead of trying to figure out what is causing the P0300, I'm going to focus on simply fixing all the other problems the car has. Such as boost/vac leaks, overheating, funky idle. Maybe, with any luck, I'll fix the P0300 in the process.

Any updates from anyone else?

Tom

bboyalan · 05-07-2008, 02:06 PM

It's nice to hear from you guys again! I was starting to wonder what happened. But yeah, glad to see you were able to clear that solenoid code. Your new approach seems worthwhile.

As for me, I haven't seen the misfire code ever since. I'll occasionally, however, get a P0420 code for my high-flow cat, but nothing major really.

Hope to see more good news!

Artago · 05-07-2008, 03:01 PM

Quote:

Originally Posted by bboyalan

It's nice to hear from you guys again! I was starting to wonder what happened. But yeah, glad to see you were able to clear that solenoid code. Your new approach seems worthwhile.

As for me, I haven't seen the misfire code ever since. I'll occasionally, however, get a P0420 code for my high-flow cat, but nothing major really.

Hope to see more good news!

So your ECU swap was finally did it eh? Or was it something else? You mentioned the TB hole you plugged and SMIC pipes slipping off. I wish an ECU swap helped me out.

Tom