Diablosport Forums

I'm having issues with my 2006 HEMI Durango and I was wondering if you could help me diagnosing if it's a wiring problem or possibly a PCM problem.

It 1st started when code P3449 DODGE - Multiple Displacement System Solenoid 7 Circuit would showed up along with a stumble and a P0300 random misfire code.

When 1st stated cold, the engine would run fine. But after a few minutes, it would start to idle very rough and stumble, smelling very rich. Then after another few minutes or so it would settle back to normal. To try and fix it and pass emission, I bought an intune and disabled MDS. It fixed the MDS code but I still have a stumble problem. So I datalogged the issue.

I can poste the logs if needed but here's one thing I noticed when it idles rough:

1/1 Short Term: 33%
2/1 Short Term 5%
1/1 Long Term 12767%
2/1 Long Term 12%

When it stumbles I can apply throttle and it effectively fixes it and the 1/1 Long Term goes back to reasonable values to match, however the stumble comes back as soon as it goes back to idle. When the stumble fades away after a while, the values also goes back to normal.

Would this be indicative of a bad PCM or could a wiring problem also cause this?

Doesnt seem like a pcm issue, would guess there is a problem somewhere. If you still get the stumble with MDS disabled and no codes, its tough to say what it might be. Checked plugs/wires/coils, etc?

mikel wrote:Doesnt seem like a pcm issue, would guess there is a problem somewhere. If you still get the stumble with MDS disabled and no codes, its tough to say what it might be. Checked plugs/wires/coils, etc?

I changed the spark plugs with no effect.

One of the reason I'm thinking it's the PCM is because other people have had similar issues and a new PCM fixed it. But info is scarce.

The other, more obvious reason I'm thinking it's the PCM is that usually, fuel trims have a range of -25% to +25%, possibly 33% for Dodge vehicles. In no way, shape or form should 12767% be considered as a remotely acceptable value. Yet this is what the PCM is commanding as per the intune. To me this leads to the PCM clearly going haywire.

But I'd like for an experience tuner to confirm that yes, these kinds of nonsensical values point to a faulty PCM.

do you have a log of those trims?
I have a feeling its just being displayed wrong.

mikel wrote:do you have a log of those trims?
I have a feeling its just being displayed wrong.

Yes, here they are.

1st one is when it's running smoothly.
2nd one, where it goes from good, to stumble, to good again.
3rd one, when it stumbles and I play with the throttle to momentarily fix it.

I don't see the ridiculous value in the actual logs. The problem might actually be the short term trim from the look of it.

Any feedback?

I noticed today that while cold and in gear, the engine would bog the exact same way, this time at throttle tip-in.

So I took another datalog. Again, on the intune screen itself, everytime it bogged, 1/1 Long Term would go from normal to 12767%. The log doesn't show that though, in fact it seems to go from 33 to -28.52 instead.

See the attached log. All the other trims seem much less erratic.