Well then.... if everything is 'new', and the wiring checks out, yet you are still seeing the same issue, something ELSE must be causing it. I have seen this before, and it is a right femaledog to figger out.

Given the pile of cash you already have invested here, I suggest picking up a cheap laptop, if you don't already have one, download PCMSCan (free version), pick up a 50 dollar cable, and start doing some data logging. Paying particular attention to what your O2 sensors are doing.

We CAN beat this.

 

Hi "Hey you",
Thanks for your reply and confidence. My confidence is not so high at this moment. Do you know what kind of cable I would need to use with this program?

I just went and disconnected the 02 sensor, and with the truck running, I took my multi-meter and put it on the DC 20V setting, and when I tested the harness it showed 1.56 V. I also put it on the ohm setting and tested the 02 sensor, and it didn't appear to be shorted out. I'm so confused.

 

Sensor should get 5 volts from the PCM.... if it isn't getting it, there is a problem somewhere. Wouldn't be the first time I have seen the EXACT same problem in a replacement PCM as there was in the original.....

It *might* be a wiring problem...... the wire may ohm test fine, but, is just a bit broken up/corroded..... so when trying to pass a bit more voltage... it fails. Those are just a blast to try and find.

Test voltage TO the sensor up at the PCM, see what you get.

Connector 1, pin 24, tan with white trace.

 

Ok...thank you. I am making notes and will take it to my mechanic. I think this is beyond me. I will have him check everything anyone mentions that may be a culprit. I also have a friend that researched this and found a thread with the following comment. This comment describes my exact same problems. I am going to try replacing the PCV valve. Apparently this can happen due to leaking oil (i.e. plenum gasket). This is the comment, and it describes precisely some of the things I have been going through...as in complete detail (only he changed many more things than I have).


"i have been plagued with this problem for a week now, i have changed TPS twice,O2 sensor twice,map sensor,distributer,rotor,pickup,coil, changed the fuel pump twice,fuel filter/regulater just this morning!! needless to say my nights of sleep have been short thinking about this.... The truck runs great till almost up to temp then idles rough,the smell of the exhaust gets stronger then the check engine light comes on even a little blue smoke.Its not the EGR valve or any of the above!!! are you ready for this one????? i was ready to burn it this morning at my wits end when i thought i should check my vacuum lines again for probably the 40th time when i touched the PCV valve and the rough idle went away.... so i popped the PCV valve out of the valve cover and cleaned it up with carb cleaner!! the PCV valve isnt computer controlled so the ECM wont tell you its the problem. See what happened is the valve wasnt working properly to recycle the engine gases when passing the unburnt gases past the O2 sensor the sensor made a reading of rich gases, so it sent a message to the ECM to lean the engine out causing the engine to run warmer than normal and give you the a fault code, when its not really a fault code but the ECM trying to tell you what reconized the problem!!! I spent a large amount of money on all these sensors and sh#t to get my BUTT KICKED by a 4$ PCV valve!!!!! CHECK YOUR PCV VALVE FIRST!!! Truck runs great cold/warm no rough idle,no hesitation, and no blue smoke easier on oil and gas!! hope it works for you!"

 

Get a pcv valve from the dealer, they actually have the correct flow rate.... a lot of the aftermarket valves do not.

 

Well...the saga continues. Very long story as short as possible. Today I had someone help me work on this. Ended up replacing the crankcase ventilation element and grommet, and the PCV valve. The crankcase ventilation element was my fault, because I thought it was the PCV valve...and I broke it - which turned into a nightmare. Regardless, that ended up being a trip to town to buy the new element, grommet and PCV valve. We also cleaned out the old PCV valve with carburetor cleaner and it cleaned up to look like new.

So I disconnected the battery and cleared the code. Started the truck and it started good, seemed to have good power. I let it run for 15 minutes - and the check engine light came back on again. I took it for a drive and it seemed to have good power, but the light was still on. So then...I proceeded to this step, which might have caused even more of a problem.

A guy at the parts house told me I should run a ground strap from the exhaust to the frame to make sure my 02 sensor was getting a good ground. I ran a ground strap from the frame to the exhaust by the front 02 sensor, and from the same frame ground to a strap by the rear 02 sensor. I cleaned up the exhaust pipe in both places to ensure a good ground. Then I started the truck, and instantly it died. Started again, instantly it died. It did not like me putting those ground straps on there at all. So I removed the ground straps, started the truck, and it barely started. It died. Started it again, and it barely idled. I let it run for a while, then took it for a drive. This time it had much less power. I even switched out the pcv valve again and put the original back in to see if that made a difference and it did not. I'm almost concerned that I somehow fried the 02 sensor when I grounded the exhaust pipe to the frame. Something happened when I did that, and it wasn't good.

So today...$80 spent for nothing between gas to town, the pcv valve, element, grommet, exhaust pipe strap, ground straps, and paying my buddy $50 to come and help me for a couple of hours (he had to drive quite a distance each way). All for nothing - day wasted - money wasted, and maybe a new problem created. I hate this truck right now.

Now I'm wondering...did I damage something by grounding the exhaust to the frame? Also I'm wondering, could the rear 02 sensor be causing a problem in all this? I have not changed it at all...ever. I don't quite understand how the rear 02 sensor fits in the picture between the front 02 sensor and the computer. Also, something I should mention, when I changed out the new PCV valve, after I had already installed it, and then put the original one back in, I noticed oil around both sides of it which I'm sure is a result of the plenum gasket.

 

Does the guy at the parts store not know that your exhaust is directly connected to the engine block? If the starter turns as it should, that ground is just fine.

I've been reading along but not commenting because the problem you've got is one I wouldn't even try to troubleshoot remotely -- and I've done many hundreds of hours of remote electronics troubleshooting. But the first place I'd start is looking at the conductors that get the oxygen sensor and the PCM connected together. First I'd check the connectors to make sure that they aren't sloppy, and if I didn't find something there I'd take the ohmmeter to those conductors, one at a time, and with the meter connected at the terminal ends I'd wiggle every inch of the conductor I'm testing while watching the meter to see if it wiggles with the wire. If it does, you've found your problem and it's a five cent fix. Two butt splices and a short piece of wire.

Oh, and don't listen to those weenies who'll gladly tell you that soldered splices are the only way to go. Where there's no vibration the soldered splice, done properly, will long outlast the crimped butt splice, but where vibration is a factor it's the other way around. That's why the factory wraps metal around its multiconductor splices; the solder is just corrosion prevention while the metal band does the work of conduction and withstanding mechanical shock. You've spent time enough on this problem already -- don't add booby traps to it.

 

Yeah, I don't see how grounding the exhaust had ANY effect. I can only reason that that your sensor is bad (again!?!?!) and that when it got a good ground, the PCM found it and didn't like it. I would definitely replace the other o2 sensor, just for grins.

As for the voltage, check it at the PCM, with and without the o2 sensor plugged. If your voltage changes significantly when the sensor is plugged in, you may have a short. I might also try to disconnect the wires for the o2 sensor at the PCM, plug your ohmmeter on to those and then wiggle the wires all of the way to the sensor, checking for an open (like Unreg suggested).

 

Thank you for everyone trying to help me with this. "HeyYou" you have really been watching and trying to help and I appreciate it. I am not a mechanic and this is just driving me nuts. I am going to compile each of the suggestions so far on this thread and print them out to give to my mechanic to check, one by one. I am going to go ahead and order this plenum kit, and schedule getting it changed, which I am sure all in all will end up being a $400 repair at least, but I don't think that will phase this specific problem I'm having now. I think, as "unregistered user" said, this is a 5 cent fix, which could cost hundreds of dollars more to find. As dbbd1 suggested, I will go ahead and change that other 02 sensor...just for grins.

If after I get the plenum fixed, and have my mechanic try each of the suggestions on this thread, if there is still no success, I guess I'll break down and take it to a Dodge Dealership, and that's when the money will fly out the window. This has got to stop.

It's really upsetting me now, because it's now cutting into my New York City trip in April to see David Gilmour in concert for his final shows in the US (probably ever in the US). In fact, this plenum just cost me tickets to see him at Radio City Music Hall. There are no words to express how unhappy that makes me. But what do you do...you have to have a vehicle that will run.

Hopefully in the end, if I can ever get this fixed, I can post the solution to this thread and perhaps the problem I'm having may prevent someone else from having to go through all this.

 

How did you secure the ground strap to the various pieces?