[JD230511]

I have an 06 3500 dodge with a cummins in it. The truck runs fine. But I notice the rpm gauge jumps around, and at idle it shows lower than what it show idle it. Anybody have any ideal what it is??

 

[Brian]

Our 04.5 Dodge with a Cummins did the same thing. It was the connection between the dash and the guage packet. Ours had a lot of dirt behind it. Once we removed the guage packet out, cleaned the connections and reinstaled, life was good.

 

[JD230511]

Thanks Brian. Was it hard to clean out?? It didn't do it on my way home from work this morning. But I noticed it last night going to work.

 

[Brian]

No, not really. I had instructions from one of the diesel forums that I followed. It was a bit ago, so I don't remember all of it. My uncle likes to leave the windows down when the truck is in the field for some reason, so the inside of ours is dirty! So, it might or might not be your issue.

Being its intermitent, it could be the motor that drives the tach or somethng in the cluster itself.

 

[JD230511]

I follow the cummins forum, ad I found out over there that its pretty common for the tach to act funny on an 06. But I'm hoping it's something simple

 

[badbradv504]

My truck is a few years older but I had same problem with my cummins and it was the crankshaft sensor. the tach gets its signal from this and when they wear out the signal can ecome erratic, hope this helps just my two cents!