Chasing ghosts
Chasing ghosts
Hoping some of you can point me in the right direction.
My '02 has two different symptoms that are driving me crazy. Might be separate issues or the part of the same problem.
Truck at times while cruising at a constant rpm with develop a random miss that comes and goes. Accelerates fine.
Other times, especially on longer trips, the idle speed will creep up and it's just a matter of time before it goes total dead pedal. I can usually pull over and kill the engine and take off again. Sometimes I have to remove the negative battery cables and let it set for awhile before proceeding. When this happens, it throws the same two codes. PO121 and PO122.
I've changed the APPS sensor to know avail. Expensive mistake.
Truck has new batteries and I've checked all grounds I can see.
Thanks in advance for any ideas.
My '02 has two different symptoms that are driving me crazy. Might be separate issues or the part of the same problem.
Truck at times while cruising at a constant rpm with develop a random miss that comes and goes. Accelerates fine.
Other times, especially on longer trips, the idle speed will creep up and it's just a matter of time before it goes total dead pedal. I can usually pull over and kill the engine and take off again. Sometimes I have to remove the negative battery cables and let it set for awhile before proceeding. When this happens, it throws the same two codes. PO121 and PO122.
I've changed the APPS sensor to know avail. Expensive mistake.
Truck has new batteries and I've checked all grounds I can see.
Thanks in advance for any ideas.
Well those are the two codes regarding the APPS sensor. Where did you get your replacement APPS? Timbo APPS is cheaper and better than OEM replacement too, just so you know.
Have you checked alternator output and AC noise?
When strange issue appear you should always remove any electrical devices added to the truck and see if the problem remains.
Have you checked alternator output and AC noise?
When strange issue appear you should always remove any electrical devices added to the truck and see if the problem remains.
Have you told Dodge that the APPS you purchased from them is still giving you grief? I'd surely let them know just in case you have a warranty period you dont want to expire while you look into other potential problems.
AC noise is basically the dirty electrical signal coming from the alternator. Some are cleaner than others but that said, AC noise was such a problem for some trucks (especially autos) that it was disrupting proper shifting.
You can check the AC noise levels with a voltage meter but the best way to understand how to do it would be to look up a video on youtube. A high tech meter isnt required either as you're not interested in the "wave" but more just the number. If its too high then its potentially causing interference with other electrical devices.
AC noise is basically the dirty electrical signal coming from the alternator. Some are cleaner than others but that said, AC noise was such a problem for some trucks (especially autos) that it was disrupting proper shifting.
You can check the AC noise levels with a voltage meter but the best way to understand how to do it would be to look up a video on youtube. A high tech meter isnt required either as you're not interested in the "wave" but more just the number. If its too high then its potentially causing interference with other electrical devices.
Great information! Thanks. The APPS is still under warranty but I have a hard time believing it failed in the same manner as the old one without there being some else causing them to fail. Like maybe AC noise now that you mentioned it.
My truck is a manual trans by the way.
My truck is a manual trans by the way.
KATOOM,
I checked out the YouTube video and it was helpful. However, I had a hard time hearing him due to the engine running through the whole clip. He might have mentioned this but what is the upper limit on A.C. voltage that would indicate a problem. His truck checked out ok so it's not useful in this sense.
Thanks
I checked out the YouTube video and it was helpful. However, I had a hard time hearing him due to the engine running through the whole clip. He might have mentioned this but what is the upper limit on A.C. voltage that would indicate a problem. His truck checked out ok so it's not useful in this sense.
Thanks
This link may help you out. Mopar1973Man's Dodge Cummins Articles - Torque Converter Lock/Unlock Issues
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It does crash while using the cruise. In fact, for a while it seemed to do it only when using the cruise so I stopped using it thinking it was isolated to that system. It ran for quite a while without any issues. Then the random miss problem raised it's ugly head and now it does it when ever it wants. May be total coincidence but the last time I had to pull the negative battery cables and let it sit to get going again was when I decided to use the cruise again as an experiment.
Ive spent so much time on this thing Im about done with it. Only thing stopping me from a new truck is a truck payment I don't want. This thing has nickel and dime me so much Ive probably bought two of these trucks.
Do what Katoom said. Check for AC noise. That is an easy and cheap fix as long as your alternator isn't shot.






