Dodge Repair Questions? Ask a Mechanic for Answers ASAP
Hello and welcome to just answer Dodge. This may be a problem with the PCM, or the connector/terminals at the sending unit. Now are you sure that you are replacing the oil pressure sending unit and not the map/boost sensor? The oil pressure sending unit is the sensor that is lower down on the engine block, and the map sensor is above the oil sending unit. They look similar and I have seen guys replace the wrong one, so double check that.
Ok, just checking to make sure that you got the right sensor. Changing the oil from synthetic will not cause this. Is there any way you can get a scan tool connected to the truck? I would like to see if the scan tool will show the actual oil pressure value that the PCM sees. Some auto parts stores may rent one to you.
I believe that I can get a scan tool to check this. The problem is that the truck is in Pa and right now I am in NY. We wanted to bring our rv up here, but since we had this problem with the truck, we left it in Pa. I only found out about this site recently, so what I would like to know is "Can we put this on hold until I go back to Pa on 6/30?" Once there I can check with the scanner and get back to you. Thanks!
Yes I can wait for you, Just reply back to this post (maybe save the email notification and just click on the link when you are ready to resume this).
I found somebody with a scan tool. It shows 99psi without engine running and same with sensor unplugged.
I'm now taking fuel filter off to check wire to ecm.
Hmm seems to me that if the ECM did see "99" psi, then the gauge would read high also. It is strange that it reads 99 with the sender disconnected. This may be n ECM problem like you are thinking. Do you have a wiring diagram for the oil pressure sending unit? If not I will send you one,
I do have a wiring diagram, but please send a copy to compare--make sure it is the same.
Found a gray wire with black tracer that goes from the oil pressure sensor to the ecm. Am trying to get a reading on this wire, but can get nothing there to give me a good reading. Sometimes get a good reading, then other times no reading at all.
Ok, here is a diagram from the factory manual for you. Hope this helps,
All 3 wires from the oil pressure sensor check good. Are there any other wires I should check?
If I run the truck with a mechanical guagewill there be any problems? Engine stopping? reduced power?
No you can run a mechanical gauge with no engine stopping or reduced power. From what you have found so far it sounds like the ECM may be the problem, and connecting a mechanical gauge would be a lot cheaper.
Do you also have a wiring diagram from the ecm to the oil pressure guage in the dash?
What woulod be your suggestion to do next?
Is there anyplace I could send the ecm to have it checked? I have it out.
Chris, Do you also have a wiring diagram from the ecm to the oil pressure guage in the dash?
What would be your suggestion to do next?
Is there anyplace I could have send the ecm to have it checked? I have it out.
There is no direct wiring from the ecm to the gauge. it is done over the PCI bus communication network. The PCI bus is the circuit that the various controllers use to communicate with each other (ECM,PCM,ABS, Instrument cluster etc.). Now it is possible that the cluster itself is failing and causing your problem. I have never seen this but it is possible. Try this for me with the ignition key off, press and hold the trip reset button on the cluster, then turn on the ignition. This should put the cluster into a self test mode. the gauges should all sweep, and the warning lights and the odometer display should cycle. Then at he end of the test there may be a code in the odometer display. If there is note it down. Check this and let me know what happens,
Did as you suggested.All the guages did sweep and the warning lights cycled. There was no code.
Ok then the cluster is not the problem. Let me do a little more research on this and I will get back to you asap.
We have heard nothing from you since July 7th. Can you be of any more help?
I'm sorry that I have not replied recently, but I did find a service bulletin that may apply to your truck. It involves having the PCM's software updated to a revised version. Here is a copy of the bulletin. Your Dodge dealer can do the update for you. Hope this helps,
This bulletin involves selectively erasing and reprogramming the Powertrain Control Module (PCM) with new software (calibration changes).
NOTE: THIS BULLETIN APPLIES TO VEHICLES EQUIPPED WITH THE 5.9L CUMMINS 12 VALVE TURBO DIESEL ENGINE BUILT BEFORE JANUARY 5, 1998 (MDH 0105XX).
Oil Pressure gauge intermittently drops to zero pressure. In addition, the warning chime may sound when the oil pressure gauge drops to zero pressure and the check gauge lamp may come on.
CAUTION: IF ENGINE OIL PRESSURE IS ZERO AT IDLE, DO NOT RUN THE ENGINE.
NOTE: WHENEVER A POWERTRAIN CONTROL MODULE (PCM) IS REPLACED DUE TO FAILURE, THE SOFTWARE OF THE REPLACEMENT CONTROLLER MUST BE VERIFIED FOR THE LATEST REVISION LEVEL. USE THE FLASH PROCEDURE TO UPDATE REPLACED CONTROLLERS AS NECESSARY.
NOTE: THE MDS2 AND DRB III® ARE REQUIRED TO PERFORM PART OF THIS REPAIR. THE MDS2 AND DRB III® MUST BE OPERATING AT CIS CD2032 OR HIGHER.
NOTE: ONCE MDS2, DRB III®, AND VEHICLE COMMUNICATION HAS BEEN ESTABLISHED, THE CANNOT READ VIN FROM DRB III® MESSAGE (ON THE MDS2) WILL BE REPLACED BY THE VEHICLE VIN. PRESS THE "OK" BUTTON ON THE MDS2 TO REQUEST A MDS2 SESSION FOR THE VEHICLE VIN INDICATED. PRESS THE "OK" BUTTON WHEN ASKED TO BEGIN SESSION.
NOTE: A MESSAGE MAY APPEAR THAT INDICATES NO UPDATES ARE AVAILABLE. IF THIS OCCURS, MAKE SURE YOUR DIAGNOSTIC EQUIPMENT IS OPERATING AT THE LATEST SOFTWARE LEVEL AS LISTED EARLIER IN THIS BULLETIN. IF THE LATEST SOFTWARE IS INSTALLED, AND NO UPDATES ARE AVAILABLE, ANOTHER VEHICLE CONDITION EXISTS THAT WILL REQUIRE FURTHER INVESTIGATION.
NOTE: A MESSAGE MAY APPEAR THAT INDICATES NO UPDATES ARE AVAILABLE. IF THIS OCCURS, MAKE SURE YOUR DIAGNOSTIC EQUIPMENT IS OPERATING AT THELATEST SOFTWARE LEVEL AS LISTED EARLIER IN THIS BULLETIN. IF THE LATEST SOFTWARE IS INSTALLED, AND NO UPDATES ARE AVAILABLE, ANOTHER VEHICLE CONDITION EXISTS THAT WILL REQUIRE FURTHER INVESTIGATION.
NOTE: THE FOLLOWING STEPS ARE REQUIRED BY LAW.
Reimbursable within the provisions of the warranty.