Hello, I have a 2000 durango that came up with the codes for the powersteering pressure switch, the running lean and of course the oxygen sensor. It was also running rough and had lots of black smoke and soot comming out of the tailpipe. I found out through this website that it was the power steering fluid leaking on the oxygen sensor making it not work right. Well I found this out after I took it to the shop and had the 02 sensor replaced. I did work fine for about 2 days then the lean code came back on and the black smoke returned. My question is now that I fixed the pressure switch and tried to clean out the wires as much as i could I still have the lean code and the black smoke. Did I clean out the right sensor? I have had so many people tell me so many different things I am not sure what do do next. Does it have 2 or 4 02 sensors? If there are 4 where are the other 2? (I know about the one before and after the CAT) Should I replace the wires on the 02 sensor? If so which one? I have been assuming it was the front. I was assuming that the 02 sensor was throwing a lean code when it wasn't really running lean that is why all of the smoke, I had someone tell me that that is not right that it is running lean but he couldn't tell me why the smoke. He told me that my computer is junk and I need to replace it, yet he couldn't give me a reason that when I fixed to 02 sensor it ran fine for 2 days. Please if anyone could direct me in what to do next I really need help figuring this out!!!! I would hate to spend the money to get a new PCM and find out that it wasn't the problem, which I don't think it is.
Thanks
J

 

an o2 sensor shouldnt cause black smoke like you described
look down into the throttle body and see if any oil is pooled up in there it might be a plenum leak.

 

Ratzo:

Sounds like you are making some progress.

IIRC, the Federal emission equipped Durangos have 1 convertor and only 2 02 sensors. 1 upstream (before convertor) and 1 downstream (after).

The models originally sold in California have two convertors, thus they have 4 sensors.

Mine was an Ohio model, so it only has 2 thankfully.

How many miles on your D, and which engine do you have???

Although the computers were a bit of an issue in the 98-99 models, the 00 versions were not near as troublesome. It is possible, but we need to rule other things out first.

Don

 

I have the 4.7 engine, 4x4, and there are 131,000 miles on it.

The only code that comes up is the p0171 so I'm thinking that the oil got into the 02 wires and it isn't able to get the right voltage running threw them to the computer. I'm not sure though and would hate to pay the mechanic to replace the wires and not have that be the problem.

It doesn't leak any oil or do I have to put any oil in between oil changes, so that kind of rules out that causing the black smoke and soot.

Any help is greatly appriciated!

Thanks

 

Ratzo:

How many miles on your plugs???? The OEM units are only good for 30-40k at best.

At 131k, I would go ahead and replace the other 02 as well just to rule it out.

If your harness is contaminated with PS fluid, there is a good chance it has wicked its way to the new sensor and contaminated it as well.

If the sensor is sending the motor bougus info, the computer is probably putting in too much fuel, causing the engine to run rich like a carburator with the choke stuck on.

If your plugs are due, I would change them as well. If they are OEM at 131k, I am surprised it runs at all.

Don

 

J,

Don is correct (Hi Don!) Your 2000 only has two O2 sensors.

The symptoms do not sound like a faulty PCM to me. I would not spend the money on that anytime in the near diagnostic future.

IMHO, you have a few issues. Leaky fluids will cause sensor issues if the fluids get into and on them. If you had a leak, after fixing the leak first of course, *throughly* clean *all* wiring contacts as soon as practical. Replace any affected sensors.

In terms of the smoke... is it tail pipe smoke or under the hood smoke? Under the hood reflects the leaky fluid burning off as it sits on the hot exhaust, etc. If it is out the tail pipe, it could be simply excessive fuel burnoff probably brought on by faulty sensor readings calling for more fuel and could be related to the above leak. It also could also be many other things so the best idea is to start small, do the cleaning and work on one variable at a time.

Good luck!

IndyDurango

 

Thank you so much for trying to help me get this figured out!!

I just replaced the plugs, so I don't think that is the issue.

As for the smoke it is coming out of the tailpipe. Everytime you start it up it leaves about a 6 inch circle of soot on the pavement. I belive it is running rich from boguss info from the sensors. So I should replace both the sensors? I didn't find out about the leak untill I had already replaced the one. I was told that it is working but is there anyway to tell if it is working correctly? It doesn't even have 60 miles on it and would hate to have replace it! But I will if that is what it takes to fix this.

I have cleaned all the connectors but that doesn't seem to make a difference. So maybe it is time to change those sensors?

Thanks again
J

 

Im sorry,maybe I missed it,but do you a check engine light on? And if so,did you get it scanned to see what codes are showing up?I mean after you replaced the p/s switch?

Thats the best way to find if there are any problems with any of the sensors.At least that way,it will be easier to narrow down.

 

I have a friend with a scanner and I also do the turn key 3 times trick. The only code that comes up now is the P0171 lean code. I think the 02 sensor is working I just don't think it is working correctly. I think it is sending bogus signals to the PCM telling it that it is running lean when it isn't so now the engine is getting way to much gas thus the black smoke and soot. I have been told so many differnent things now by different people I just am not sure that I'm right.

I was also wondering if there was anyway to tell if my new 02 sensor has been contaminated with the oil? If I pull it out will I be able to see the oil?

Thanks
J

 

J:

Sorry that this is so frustrating for you. Please understand that it hard to diagnose an issue through the computer when we can't see what you are seeing and hearing.

Some of the folks here do turn wrenches for a living, or have at one time. I would not be one of them. I am guilty of spending to much time surfing these forums since I am a car guy through and through.

There is a wealth of info her about Durangos, and between this forum and another one I have pretty much fixed any issues that come up with my rig.

Back to your issue. Which 02 did your replace?? If it was the downstream unit, your issue may in reality be the upstream unit. IIRC, the upstream is the one that tells the computer what fuel mixture is, and the downsrteam is there only to verify that the cat-con is working properly.

Common sense says that the upstream unit sees more heat being closer to the engine, and generally dies before the downstream unit.

02 sensors usually either work or not. They create a small voltage based upon the mixture they see, and the signal is either hi or low.


Does the engine seem to be missing at all? You say it it running rough. How is the operating temp?? Is the temp guage getting up to where it should be after it warms up?

If not, the coolant temp sensor will keep the computer in closed loop which is similar to leaving the choke on on an engine of old.

Don