420A Losing Power, Sputtering, P0300, P0301, P0304 CELs Need Help!

[Abob]

I've done some searching on here to try and find out what is going on with my car but I just can't seem to find anything similar.
My car is running like crap cruising down the road. It starts fine but when I start going it goes to crap. I pulled a few codes, p0300, p0301, p0304, and a couple evap ones. One was no flow and the other was small leak.

Anyway, it doesn't do it all the time. It will be fine for a few days or more, then go crappy for awhile. Back and forth like that. Sometimes it will do it when I start out, like the start of 2nd gear, then go away. Sometimes it won't go away for awhile. Other times it will do that when I'm cruising in 5th gear on the highway or no matter what gear or speed. It seems to loose power, and just run on 2 cylinders. Sputtering, spitting as well as the check engine light flashing at me.

I have changed plugs, wires, coil pack, and check the fuel filter ( its clean). I've been told of a few things have beendone to the car such as exhaust, header, cams.

 

[Abob]

Well gee I guess the ecu for your car is in the engine compartment, which I didn't know.
It is called a PCM in most places in the manual.
Since it is right there where you can see it, you could look at the wires going into it to check for hacking pretty easily, without taking anything apart.

Looks like it has 2 connectors, 40 wires going to each one. They are labeled 106 and 107 in the manual.
It might be worthwhile to take the connectors off and look for corrosion or damage on the individual connectors inside. There could be corrosion, especially if they salt the roads there. The 2 wires to the coil are in 106. I think the wires to the injectors are in 107.
Here's the big picture, in case you don't already know where this thing is. I marked the good stuff in blue:

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You know I was starting to think the same thing, because I found some yellow paint numbers on the PCM. What that tells me is it is from a junkyard and the P O had it replaced at some point in time.

 

[We're on Boost]

You know I was starting to think the same thing, because I found some yellow paint numbers on the PCM. What that tells me is it is from a junkyard and the P O had it replaced at some point in time.

Hmmm. Interesting.
It could be bad inside then, like the used one I got.

 

[Phantom DSM]

Hmmm. Interesting.
It could be bad inside then, like the used one I got.

^^ This. The man is right, it could be PCM last resort if everything else checks out.
As for the filler neck, yes check that and any vacuum hoses in the front , fuel vapors or small leak in the system could trigger that Evap leak as well. I will look that up, as there have been reported cases of fuel vapor leaks iirc

 

[Abob]

OK so I took off in the car this morning and its like it was before. It has been doing it all morning. I pulled the new plugs and they are black around the outside and almost like a carbon build up in the center. I think she's running bad rich for some reason. I have pics of the plugs but I can't get them to upload

^^ This. The man is right, it could be PCM last resort if everything else checks out.
As for the filler neck, yes check that and any vacuum hoses in the front , fuel vapors or small leak in the system could trigger that Evap leak as well. I will look that up, as there have been reported cases of fuel vapor leaks iirc

Even tho it ran great for like 2 months after I got it? Hmm

So I gained another problem. If I let 2nd gear stay at about 2500-3000 rpms and try to take off it stutters and bogs down. Similar to what happens with a clogged converter. The same goes if I try to take off fast from a stop. Living by a busy highway sucks Lol

 

[We're on Boost]

I have pics of the plugs but I can't get them to upload

If the forum's own photo upload thing is working, it's the easiest way. You have to scroll down the page a ways to see the button, which is a wide gray button called "Upload/Edit Photos". Then that brings up a little pop-up window where you can tell it where to find the picture on your computer. This way of doing it does dumb-down the picture quality quite a bit.

If you want the best picture quality, the way I've found that is the best is by putting your picture into Image Shack with their upload dialog set to "Do not resize". Then Image Shack will have a copy of your picture that is bit for bit the same (I think) as the original you have on your computer. Then you copy the link they call the "Direct" link, and paste that into the field that you get from the "Insert Image" icon here in the forum (first delete the text in that field so it is blank when you paste in the address). That method is kind of complicated if you are not already an Image Shack user but I could step you through it if you want. I think Image Shack makes you register to get started these days. Anyway the quality you get that way is I think bit for bit the same or very close as what you get out of your camera or screen shot or whatever.

When you pulled the plugs this time, did you pull all 4? I'm wondering if all 4 plugs looked dirty, or if it is just the plugs in 1 and 4.

 

[Abob]

I pulled all 4 plugs and they all looked very similar. Black with carbon build up.

Got pic 1-4 left to right. Second pic is the plugs that were in it when I got the car

 

[We're on Boost]

Well the old ones look like they've been in there for a while, but given that, they don't really look bad. Just a lot of erosion from use.

The new ones don't look fouled or bad in any way that I can see. The 2 on the right have darker outer electrodes I think, than the 2 on the left. Do you know which cylinders the 2 on the right came from?

 

[Abob]

Well the old ones look like they've been in there for a while, but given that, they don't really look bad. Just a lot of erosion from use.

The new ones don't look fouled or bad in any way that I can see. The 2 on the right have darker outer electrodes I think, than the 2 on the left. Do you know which cylinders the 2 on the right came from?

They are all laying in order left to right. Far left is cylinder 1 and continue in order.

Well I replaced the coil pack today with a used one. Still got the same result as before. Now if I try to run any higher than 4k rpms it stutters, buck, and carries on like it hitting a fuel cut out. This is by far the worst I have ever experienced with a car. I think I would rather deal with a few spun rod bearings than this.

 

[Phantom DSM]

They are all laying in order left to right. Far left is cylinder 1 and continue in order.

Well I replaced the coil pack today with a used one. Still got the same result as before. Now if I try to run any higher than 4k rpms it stutters, buck, and carries on like it hitting a fuel cut out. This is by far the worst I have ever experienced with a car. I think I would rather deal with a few spun rod bearings than this.

Sorry to hear man, Im scratching my head on this one. With the used coil now, does it register any cel's? good ohm reading on it ? Last resort, maybe ecu.

 

[We're on Boost]

Yeah this is a tough one. But then they usually are!

I thought we might be able to tell just by looking which plugs came from 1-4 and which from 2-3. But I don't see it. So given that, it might not be just the 1-4 coil circuit. It might be something that could cause more widespread trouble, like a crank position sensor, cam position sensor, or maybe something else that we haven't thought of yet. When I get a chance I could see what there is for testing the cam/crank position sensor. Oh maybe the MAF too. I've never had cam/crank position sensor trouble myself, so don't really know how it would act.

It still could very well be the PCM. If you had a way of getting one to try temporarily, that would be pretty cool. Looking for rebuilt/inspected PCMs with a guarantee on the web I'm finding them only for automatic, for about $100. Is yours an automatic tranny? Well OK I see them for manual tranny too. Usually $200 with a Lifetime warranty which I suppose means they'll replace it with another one, but I doubt you'd be able to get your money back on the ones I'm seeing.

Well, just looking through the OBD-II codes available for the car, I see codes for just about everything mentioned above. If you aren't getting any of these codes, then probably the cam and crank sensors etc are ok.
I'll mention the ones that seem relevant here:

P1391 - Intermittent loss of CMP (cam position sensor) or CKP (crank position sensor). This code seems close to what you have going, but apparently you aren't getting this code.

P0351 - Ignition coil #1 primary circuit
P0352 - Ignition coil #2 primary circuit
P0340 - No cam signal at PCM or cam position circuit malfunction
P0605 - Internal controller failure or PCM failure - SPI communications (warning - I don't think ecus are very smart about knowing when they have failed).
P1300 - Ignition timing adjustment circuit malfunction
P0100 - Volume air flow circuit malfunction (MAF)
P0105 - Barometric pressure circuit malfunction
P0130 - O2 sensor circuit malfunction
P0170 - Fuel trim malfunction
P0171 - Fuel system Lean
P0172 - Fuel system Rich
P0201 thru P0204 - Injectors 1 thru 4 control circuit
P0335 - No crankshaft reference signal at PCM or crankshaft sensor circuit malfunction.

So if the only codes you are getting are the evap codes and these:
P0300 - Multiple cylinder misfire (M/T) or Random misfire detected
P0301 - Cylinder #1 misfire
P0304 - Cylinder #4 misfire

Then, it seems like the problem has to be the stuff we've talked about, the coil pack, harness and connectors between PCM and coil, plugs and plug wires, and PCM.
All those things seem to check out OK, except that I don't think we know how to reliably check out the PCM, so that's probably what it is - the PCM.

I would try unplugging those 2 connectors (106 and 107) from the PCM, looking at them, and plugging them back in if they look ok. If it is some surface corrosion in there causing intermittent contact, you might scrape it off just by the act of unplugging and re-plugging those 2 connectors.

Maybe it could also be dirt in the injectors/fuel rail or some other non-electrical problem with the injectors.

 

[Abob]

You know I was starting to think the can or crank sensors had something to do with it, but for some reason I'm stuck on it being a fuel issue. I'm going to pull the cover off the tank under the rear seat and inspect the pump. As well as take a more indept look into the fuel filter. I will also pull the PCM connectors and take a look at them. I've got the shop warming up now

Just want to say thank you to everyone helping me on this. I'm glad I found this site.

So I got the car up in the air, and found that my 2nd o2 sensor is busted off and wires are just hanging there. Hmm. would this have anything to do with what I am experiencing

I uploaded a video of the car idling like crap. I wish I would have got the video sooner. You could her my intake taking in a lot of air trying to stay idling. The video is on my Facebook page. My name is Andrew Clang

 

[David9er]

for some reason I'm stuck on it being a fuel issue. I'm going to pull the cover off the tank under the rear seat and inspect the pump. As well as take a more indept look into the fuel filter.

So I got the car up in the air, and found that my 2nd o2 sensor is busted off and wires are just hanging there. Hmm. would this have anything to do with what I am experiencing

A lack of fuel is possible, have you looked at the fuel pressure regulator? you could also switch the injectors around to see if the misfire follows it, same with the plugs, wires, and even the two coils

The second O2 sensor is more for emissions than drivability but it could be a cause so get it fixed clear the codes and start over.

 

[We're on Boost]

If you get the fuel filter taken apart you might as well put a new element in it. They don't cost much.

If you do take out your injectors for any reason you have to be pretty careful about how you put it all back together, and the manuals all say to put new O-rings on them for reassembly. The old ones get hard and take a set after that many years, and they could leak fuel if reused. Kind of like how Richard Feynman had to show all the NASA wienies that the O-rings in the SRBs were no good - except that was due to cold, and this is due to aging in gasoline!

Also if you do take out your injectors, see if you can blow out the fuel rail with compressed air, or in whatever way make sure there is no dirt kicking around inside the fuel rail. Also make sure there is no dirt coming out of your air nozzle!

It would be a good idea to get the 2nd O2 sensor replaced, although I also don't think it should really affect running.
What bothers me more about that is, there are OBD-II codes for that, and apparently you didn't get them. What the heck?
I think the codes would be:

P0136 - O2 sensor circuit malfunction (bank 1 sensor 2)
P0141 - O2 sensor heater circuit malfunction (bank 1 sensor 2)

Which brings up - how are you getting your codes? Do you have your own code reader, or are you going to Autozone or someplace?

I don't have a facebook account so I guess I won't be able to see the video unless you can post it someplace else.

 

[David9er]

It would be a good idea to get the 2nd O2 sensor replaced, although I also don't think it should really affect running.

The ECU does use this sensor for emissions control so it is possible it is reading low O2 and cutting the fuel

What bothers me more about that is, there are OBD-II codes for that, and apparently you didn't get them. What the heck?
I think the codes would be:

P0136 - O2 sensor circuit malfunction (bank 1 sensor 2)
P0141 - O2 sensor heater circuit malfunction (bank 1 sensor 2)

As long as part of the sensor is still there the electrical circuit may still be complete so the ECU does not detect a fault

my 2nd o2 sensor is busted off and wires are just hanging there.

 

[Abob]

Hmm. I wish it was cutting fuel. Lol. I've put around 60 miles on the car and Burne 1/4 of a tank.

To be honest I'm not sire where the fuel pressure regulator is on this car.

I'm getting my codes from the auto zone scanner

 

[David9er]

^Yeah you gotta get this fixed first. Like I said it is possible the ECU is trying to control emissions but is getting a false reading from that sensor. [BTW are those wires touching each other at all? If not then like "we're on boost" said it should be throwing a code for that too.].

The fuel pressure regulator will be on the end of the fuel rail. But first clear the codes and move the #1 and #4 injectors to the #2 and #3positions and vice versa to see if the misfire follows the injectors.

If not I have a sneaking suspicion that it is your coil for the #1 and #4 plugs or the wiring going to it. When you reach this point swap the coil positions, clear codes and see where the misfire is. If it has not moved then check for continuity in the wiring from the coil to the ECU. Just because a coil gets good continuity readings does not guarantee it is a good coil.

Fuel system issues normally cause only random misfires because they affect all the cylinders [except the injectors] so lets hold off on the regulator, pump, and filter till later.

 

[We're on Boost]

Well, I can't tell for sure how much is left on the end of that cable, but it doesn't look like much is left! I kinda think it should be throwing a code.

So I'm thinking you are not getting all the codes you should be getting when you go to Autozone.
When you go there, does an AZ person go out there with the scanner and do it for you? Or do they hand you the scanner and you do it yourself?
I'm thinking either they are not reading the codes all the way through to the end (which sometimes takes a few minutes) or for some other reason (maybe a bad PCM) you are not getting all the codes.

I think you should try reading the codes manually, without a scanner. Maybe you'll come up with a few new codes you weren't getting from autozone. I'll copy the instructions for that from the Chilton manual (pages 4-35 and 4-36). Hopefully they are correct. I've never tried this on an OBD-II car, so can't verify. My car, OBD-I, uses a completely different method.

I can probably also find you a picture of how the fuel pressure regulator goes on.

Basically, when it stops blinking for 4 seconds it is moving on to the next code. I don't know how it tells you a 0. But try this out - it's easy.
Step 4 is just if you want to clear the codes that are stored in the PCM.

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[Abob]

I tried that and it does work. Will post codes later

So I got the codes
12, 17, 43, 43, 43, 31, 31, 55

That's the order it flashed in. I'm not sure why I got 43 in a row 3 times and 31 two times in a row. But those numbers are how it flashed

http://www.2gnt.com/index.php?d=PCM Error Codes

So basically my ignition system for some reason is still bad, or I have a load of other possibilities. As well as the o2 sensor causing problems. Hmm interesting. I love the old cel light flash. Lol.

 

[We're on Boost]

Cool! Glad that worked.
I'll take a look and see what I can make of it.

 

[Phantom DSM]

I tried that and it does work. Will post codes later

So I got the codes
12, 17, 43, 43, 43, 31, 31, 55

That's the order it flashed in. I'm not sure why I got 43 in a row 3 times and 31 two times in a row. But those numbers are how it flashed

2GNT.com - PCM_Error_Codes

So basically my ignition system for some reason is still bad, or I have a load of other possibilities. As well as the o2 sensor causing problems. Hmm interesting. I love the old cel light flash. Lol.

Judging from the diagnostic list, code 43 is listed multiple times because it is generating a multiple cylinder misfire and a 2 seperate cylinders counted misfiring, just not specific. This is where the scanner comes in handy to narrow down .
It starts with P0300 for the random and the final digit is the cylinder number..0301,0302etc. You can use the scanner again to narrow it down. The evap codes are still present, but im very surprised the downstream o2 sensor codes did not pop up considering condition of harness in pic
The generator code is weird, do you have an issue at your Alternator harness plug ?

 

[We're on Boost]

Yeah, I see that method doesn't differentiate some of the things that need to be differentiated.

The 43 given 3 times is probably codes P0300, P0301, P0304, which you had before from the scanner.

12 - I think just means that you disconnected a battery terminal sometime in the last 50 key turns.

31- the evap stuff.

17 - Now this could be interesting. This is code P0125 which I don't think we had in the discussion before. "Closed loop temperature not reached". This could be more serious than it sounds. Also, googling P0125 I get some differing descriptions from different people.

I'm thinking, if your car never reaches closed loop temperature it will forever be running without any smarts from the front O2 sensor, even if the front O2 sensor itself is OK. It will be running open loop all the time. Or if it just thinks it is too cold but it's really not, it will be running too rich. You might not get a P0172 (too rich) because it would be running open loop and wouldn't know that it's too rich. I think.

What I see googling around on P0125 is that it could be the actual coolant temperature (bad thermostat), or a bad engine coolant temperature sensor (sending a bogus signal to the ecu). I also see some people saying it could be a bad heater circuit in the O2 sensor (replace O2 sensor, or fix wires or connector. Your O2 sensors are heated). I think I saw 1 or 2 other suggestions also.

If your engine never gets into closed loop, I think it could cause some bad running. On the other hand, if it is just slow getting into closed loop, but does get there after a few minutes, I wouldn't think it would be as bad as what you have.

So I think this code P0125 is worth fixing, whatever it takes to do it, it might fix the problem.

 

[Phantom DSM]

Yeah, I see that method doesn't differentiate some of the things that need to be differentiated.

The 43 given 3 times is probably codes P0300, P0301, P0304, which you had before from the scanner.

12 - I think just means that you disconnected a battery terminal sometime in the last 50 key turns.

31- the evap stuff.

17 - Now this could be interesting. This is code P0125 which I don't think we had in the discussion before. "Closed loop temperature not reached". This could be more serious than it sounds. Also, googling P0125 I get some differing descriptions from different people.

I'm thinking, if your car never reaches closed loop temperature it will forever be running without any smarts from the front O2 sensor, even if the front O2 sensor itself is OK. It will be running open loop all the time. Or if it just thinks it is too cold but it's really not, it will be running too rich. You might not get a P0172 (too rich) because it would be running open loop and wouldn't know that it's too rich. I think.

What I see googling around on P0125 is that it could be the actual coolant temperature (bad thermostat), or a bad engine coolant temperature sensor (sending a bogus signal to the ecu). I also see some people saying it could be a bad heater circuit in the O2 sensor (replace O2 sensor, or fix wires or connector. Your O2 sensors are heated). I think I saw 1 or 2 other suggestions also.

If your engine never gets into closed loop, I think it could cause some bad running. On the other hand, if it is just slow getting into closed loop, but does get there after a few minutes, I wouldn't think it would be as bad as what you have.

So I think this code P0125 is worth fixing, whatever it takes to do it, it might fix the problem.

Great info right here I lost track of code 17when i was looking at msfire numbers. Im very surprised P0125 did not come up on the scanner on the first round of testing when this thread started, would have explained the issue with excessive fuel
In the manual here p0125 is listed as "Closed loop temperature not reached (M/T)" and also "Excessive time to enter closed loop fuel control"

 

[We're on Boost]

Yes, it would be great if fixing the -17- took care of it. We can keep plugging away at it and see what happens. Hopefully Andrew won't have to replace his PCM.

 

[Abob]

I believe code 17 is from my thermostat. The PO put a fail safe thermostat in the car, so if the car gets to hot it sticks open. I didn't realize they made such thing. Lol. I reset it and have since ran at normal temp. Although that stupid thermostat doesn't take much to stick back open.

I'm going to start tracing the wires for the coil pack, as well as the injectors. To see if I over looked a bare or broken wire. I am also going to try and get my hands on another coil pack, just to double check it.

I will be ordering my o2 sensor tonight, so I can get it straightened out. I did notice that the plug for the o2 sensor is in the car. Where would in be inside the cab?

 

[Phantom DSM]

I believe code 17 is from my thermostat. The PO put a fail safe thermostat in the car, so if the car gets to hot it sticks open. I didn't realize they made such thing. Lol. I reset it and have since ran at normal temp. Although that stupid thermostat doesn't take much to stick back open.

I'm going to start tracing the wires for the coil pack, as well as the injectors. To see if I over looked a bare or broken wire. I am also going to try and get my hands on another coil pack, just to double check it.

I will be ordering my o2 sensor tonight, so I can get it straightened out. I did notice that the plug for the o2 sensor is in the car. Where would in be inside the cab?

I believe in the 2gs, its under the carpet behind driver seat sort of. Check your coolant temperature sensor as well and swap out to correct tmeperatur themostat as well. If all this doesnt start producing good results, then as We're on Boost has been on a good hunch, the PCM is crapping out.