CEL: Too rich. Possible solutions?

[yellerandahalf]

Hello again, I have another problem as usual. To start out, if you don't know me, I'm not an idiot, I'm attempting to get my MSP back to stock with motor #3. It's running pretty well, all considering, but I have a single CEL: bank one too rich.
it doesn't warm up properly, but cruises fine, and eats a little more gas than usual.
What I need help with is to form a list of possible items that could be causing this, so that I can go through and check out each one.

Here's what I think might be potential problems:
-EGR pipe (new) isn't all the way tight on the intake side (couldn't get a wrench in there, it's as tight as I could get it. it's tight, but not flush. I have tried unplugging the EGR valve, does not have an effect.
-vacuum leak (checked obvious places, retightened all clamps, etc, haven't found anything.
-bad O2 sensor-not yet checked.
-bad PCM-god I hope not.

any other ideas would be greatly appreciated. Many thanks.

-Matt McBride

 

[cosmo420]

I have the same prob but I think it is due to my unichip after a couple of days I get the code from my data logger saying bank one too rich, so I re-set it and I am good for a couple of days, then again it might be the o2 as well, I hope not either the last time I paid for it was about 250 or so. as far as the egr bolts go it is a tuffy but not impossible, one just has to be a little patient, my fingers and hand would go numb, but I got it done.

 

[kudakev615]

i can get on mitchell and do some research if you can give me exact code its throwing. but you on the right track with lookin at vac lines. some thing like that is usually what will effect a whole bank of cylinders, not just one. the egr is possible, but not likely. let me know if i can help

 

[namdlo]

I'm running into a very similar issue. The code for the "fuel too rich: Bank 1" is P0172. I started to get this the other day as well. I removed the upper pipe and heat shield to get the o2 sensor out. Nothing looked out of the ordinary on any of them. Put the o2 sensor and pipe back on (left off the heat shield) and sprayed the pipe connections with starter fluid to see if I had a leak - nothing. The car ran the best it has probably ever run for about 20miles and then started shuttering and bogging down again. When accelerating I can boost up to 8lbs but the car just doesn't seem to get up and go -- very slugish. Another thing that I noticed when the car is running "right" letting off the gas is a smooth transition while other times the car seems to shutter down 2 steps. The car is running very rich and likes to backfire quite a bit. My upgrades are: corksport s and j pipes, corksport exhaust (no cats), non-fouler solution for no cats, forge bov and unichip. Please let me know if I'm going down the right path to solve this issue. I'm going to check all of the vacuum lines. Replace the spark plugs (I have IK22s waiting). Re-install the original bypass value. I've reset the ECU and Unichip recently - no help. I'll post with any results of the changes.

 

[namdlo]

The damn CEL came back this afternoon.

 

[cosmo420]

I'm running into a very similar issue. The code for the "fuel too rich: Bank 1" is P0172. I started to get this the other day as well. I removed the upper pipe and heat shield to get the o2 sensor out. Nothing looked out of the ordinary on any of them. Put the o2 sensor and pipe back on (left off the heat shield) and sprayed the pipe connections with starter fluid to see if I had a leak - nothing. The car ran the best it has probably ever run for about 20miles and then started shuttering and bogging down again. When accelerating I can boost up to 8lbs but the car just doesn't seem to get up and go -- very slugish. Another thing that I noticed when the car is running "right" letting off the gas is a smooth transition while other times the car seems to shutter down 2 steps. The car is running very rich and likes to backfire quite a bit. My upgrades are: corksport s and j pipes, corksport exhaust (no cats), non-fouler solution for no cats, forge bov and unichip. Please let me know if I'm going down the right path to solve this issue. I'm going to check all of the vacuum lines. Replace the spark plugs (I have IK22s waiting). Re-install the original bypass value. I've reset the ECU and Unichip recently - no help. I'll post with any results of the changes.

I swear that is THE EXACT thing I am having an issue with that is driving me into the poor house, I have one last gander that I am trying to put off and that is to buy an o2 sensor, and now I noticed a little oil consumption ( about a 1/4 of a qt. every 3 weeks or so, with no wet plugs, no leaks, and no oil smoke, even under hard acceleration, and oh yes no leaks inside the turbo inlet, but itis there so I will be paying attention to your inquiry will well interest
of course code p0172 is there to pay me a visit almost ever 3 days

 

[ZenProtege]

Hmmm, man...just to throw some thoughts out there...With having changed engines three times, it seems like a vac leak would be your most likely culprit.

If you had an exhaust leak that was causing your primary 02 sensor to see less exhaust flow, I imagine it would be accompanied by another DTC such as 'egr insufficient flow' that would enforce a leak as the cause.

If your egr was malfunctioning to the extent that it was preventing your PCM from maintaining proper AFR's, I imagine you would have thrown an egr related cel with the lean bank 1 code by now. So in other words, I doubt an exhaust leak or EGR valve are your problem.

For your 02 sensor as the potential cause, maybe. 02 sensors like spark plugs, need to be replaced though seldom. If you have access to a shop with a labscope, that's is the most accurate way I know of to determine if it's ok. Maybe you can do a similar test with a DVOM and Propane cylinder. Since the sensor is functioning and should still have plenty of life left in it, I don't see your O2 senser as a likely suspect.

I would get a vac pump and check all my vac lines, and if that didn't indicate anything I would check the IC piping for leaks. Best of luck troubleshooting your problem,
-zen

 

[CitizenPro]

i get the same "too rich" code every now and then as well.

 

[JDM Sam]

Vac leak will cause a lean condition not a rich condition.

Check the voltage to the front o2 sensor, only way to test its function.
Check your purge solenoid the s*** bolted on the cold pipe with 2 hoses or fuel pressure regulator solenoid the black plastic s*** bolted by the throttle body.

 

[yellerandahalf]

I have heard of vacuum leaks causing too lean and too rich conditions. I don't think it's an O2 sensor problem, because I tested it, and it's functioning properly, fluctuating normally at idle from about .25V to about .85V.

To clarify, I didn't have a problem getting the bolts that bolt the EGR onto the motor; it never came off. I'm having problems screwing the EGR TUBE into the EGR vavle. I'm concerned that that may be causing a vacuum leak. I couldn't get it to bottom out, but I did get it tight. very frutstrating.

Either way, I would think that if you unplug the EGR, it would cancel out that leak if there is one, because the valve would never open. I tried it and nothing happened. grr.

JDM Sam, how does one check the purge solenoid and the fuel pressure solenoid? I know what you're talking about with them at least.

I think I'm going to try the spraying lighter fluid trick and see how that turns out. Until then, I'm as stumped as usual.
-Matt

 

[MazdaBoi318]

i hope it works out for you man....

 

[ZenProtege]

ooooops, I thought I read bank 1 too lean, not rich. Nonetheless, a vaccum leak (post-maf )that comes out under boost could still be the problem.

If your egr was stuck open I would have expected to hear that the car was 'running horrible and idling like ass'. I don't think that's your problem.

I still have a feeling that your problem is vac-related. Guess #2 is your Maf. Have you checked the shop guide yet?

 

[namdlo]

FIXED

I actually had a couple of problems. The first issue -- I was missing a nut off my turbo (wasn't sealing properly). The second issue -- I removed the EGR to clean it -- it was pretty dirty and the spring was sticking -- cleaned the EGR and oiled the spring, it's like having a new car

I've got a friend that works as a mechanic and he's going to pull the turbo at the end of the month to put on my S-pipe and clean my injectors for me so we'll see how she runs after that.

Thanks for the suggestions everyone.

 

[slowmotionmsp]

FIXED

I actually had a couple of problems. The first issue -- I was missing a nut off my turbo (wasn't sealing properly). The second issue -- I removed the EGR to clean it -- it was pretty dirty and the spring was sticking -- cleaned the EGR and oiled the spring, it's like having a new car

I've got a friend that works as a mechanic and he's going to pull the turbo at the end of the month to put on my S-pipe and clean my injectors for me so we'll see how she runs after that.

Thanks for the suggestions everyone.

The missing nut on your turbo must be a common problem, i had found similar issue with my car. Also, the gasket was blown on the header that connects to the turbo. It's all fixed now, though. I think people who have their cars under warranty should have it looked at under warranty while they can.