Here is the problem. I keep having to replace o2 sensors in the durango. Most common code i get is the p0171 (system to lean). A week ago i had six codes p0131, p0132, p0137, p0138, p0141 and the 1 above. It also started stalling at stop lights and loosing power while driving. Only way it would go is if i floored it. After changing the plugs and clearing the codes i drove 50 miles before getting the p0171 and the p0137 codes it was driving crappy again. Have replaced converter, fuel pump and many o2's. Now today i have replaced the coolant temp sensor, the down stream o2, checked for vacuum leaks, checked engine vacuum, which by the way was 17in of vacuum and then looked at the plug for the up stream o2 for the pwr steering fluid problem of shorting it out. There was oil in the plug but nothing on the harness. I also took out the map sensor and it had alot of carbon on it so i cleaned it. Not sure if that was a good thing or not. Took it for a drive and 3 miles later code p0171 and same crappy idle and drivability. So my question is should i replace the up stream o2? Is it fighting the other one? What do you think about the map sensor? Thanks.

 

Ok, as a do more looking on the web i find that it was not the map sensor i cleaned. Not sure what the sensor was. It is located on the driver side of the plenum next to the hose that comes from the brake booster. But did take the map sensor out and it seemed to look good. o ring was in good shape and nothing was plugged. Could it still be a possible problem?

 

Ck the power steering switch for any leaks. Its very common when the switch leaks, the p/s fluid leaks into the harness and short out the o2 sensors.

 

I did find oil in the upstream o2 connector but not on the outside of the harness. I found a post describing the power steering switch leaking into the harness and traveling thru the insulation of the wires to the connector. That makes sense since i found oil in the connector but not on the outside. If this is so, i got part numbers to create a separate harness for the o2 sensor. I will look more extensively at it tomorrow.

 

Here is what I have done, spray brake cleaner into the p/s connector and disconnect the 02 sensor and with a blow gun with air and try to push some of the oil out. Then let oil drip from the connectors overnite. If that doesn't work then you'll need to replace the harness or wire over lay for the 02 sensors. Also replace the p/s switch too.

 

Is the theory that the oil travels into the sensor and shorts it out? Or that it shorts it out in the connector?

 

No,Theory it really does. The oil could also travel all the way to the pcm connector too.

 

Well i am convinced that it is the pwr steering switch. I pulled apart the o2 connector and more oil came out. Pulled the connector off the pwr steering switch and it is leaking. I was going to rewire the ground wire of the o2 since that seems to be the problem but decided i will get the harness that dodge sells for the fix. I read on another site that they sell one. I also cut the two wires for the pwr steering switch and then spliced them with connectors so that the leaking will come thru those if this should happen again and keep it from reaching the pcm as you discribed. I have to use the Durango this week to get around, so i unhooked to upstream o2 and the truck is running back to normal. The engine light is on but that is expected. I will update this when i get the fix done. Thank Master tech.

 

Interesting problem. Hopefully this will take care of the issue for you.

 

I had heard about this problem when i started to try and figure out what was going on but i would have never thought that pwr steering fluid could travel 5' or more thru wires. But after researching the problem, it turns out the connector for the pwr steering switch can hold 100 pounds of pressure. So when the switch leaks, it leaks into the connector and pushes it into the wires where the o2 and pwr steering switch wires share a common ground behind the motor. When the fluid reaches this point it travels into the connector of the o2 sensor and shorts it out. It can happen to all o2 sensors and as master tech said, it can eventually reach the pcm. If anyone else with similar problems should read this, you can at a minimum 1 look to see if the pwr steering switch is leaking. Pull the connector off the switch to see the leak and 2 pull the connector/s of the o2's to see if there is fluid in them. I have spent $1500 or more at several mechanics and dodge themselves only to diagnos the problem myself. I thought at least dodge would have known this. Like i said, didn't think that it could happen but it did. Thanks guys for all the input. Even when i posted the wrong year.