Freightliner Columbia Problem

I have a weird problem with my father's 07 Columbia (merc powered) and after many mechanic visits, they cannot find a solution.

Initially, I would start the truck and after a few seconds to a few minutes it would turn off. All fluid levels were fine and I decided to take it to a shop. The shop kept it for a week and checked all the electricals and did not find the problem. He then changed the ECM and put a used one and returned the truck. I drove this truck about 300 miles and the problem came back. I was under a load.

I managed to deliver the load and get into another shop. They put it on diagnostic and found no codes. However, they said it looks like the module and/or harness behind passenger seat is at fault. They couldn't fix the and put a ground wire into the module and said you should be able to get it back home.

When I got home, I took it to another mechanic and he went over everything again and changed the above harness. Problem was still there. He dropped it off to the dealer to get the above module reprogrammed. The dealer did not program it because they said the module doesn't match with the VIN. Also, now I the rpm don't go past 1500, odometer does not work and also some lights.

Did anyone on here experience such issue? Can you help.

Thank you

 

I changed the ECM back to the original. Still no change. The third mechanic said, he can direct the VCU (located behind passenger seat- b piller) but that might cause some burnout.

I agree, I took it to way too many mechanics but I had no other option. I am not thinking of dropping it at the dealer, since they looked at it before.

 

The truck turns off every few seconds to few minutes. Now, after a few visits to mechanic, also the acceleration needle does not move and the rpm don't go past 1500.

 

Harness and all the electrical has been checked many times. I am leaning towards mechanical rather then electrical.

Should I be mentioning everything you said to the mechanic?

 

I would sell it but we are the second owner, truck has been paid for and for the little work my dad does, i feel this is perfect. Other then this issue, everything else is great.