I have a guy that did a transmission swap to a manual. He changed the ecm, every thing works and there are no trouble codes but when he starts it it does a lope for a minuet or two then it goes back to normal. Any ideas of what i could be?

 

What year/model? What is the PCM code of the donor PCM?

 

IS it like a cold start lope, or an aggressive cam lope?

 

THe ICP sensor can cause the lope as well as the PCM not seeing signal from the TRS ..

 

Not if it's a manual PCM. A manual PCM has no clue what a TRS is. But that's the reason for the question re. the PCM code; the PCM swap could easily have amounted to replacing one auto PCM with another.

Oh - another question for the OP - is a chip/progranner/tuner in the picture?

 

I kinda know about the manual PCM Thing . Only time I have seen romps on a manual trans was from the incorrect PCM looking for signal from TRS or the ICP mod or bad connection or bad ICP sensor

 

I had this issue. Having my PCM reprogrammed resolved it.

 

It is a 97 f350. I dont know what the pcm code is. He got the transmission out of a running truck and took the ecm from the truck with the manual transmission should he swap the pcm as well?

 

There is no ECM. The PCM runs the engine (and, on automatic-equipped trucks, the transmission). Look at the harness connector on the PCM on the under-hood side for a four-character (three letters, one number) code. You may need an inspection mirror. If that label is unreadable, remove the nuts holding the parking brake pedal/release assembly to the side wall of the cab, and pull the assembly away from the cab wall (no need to disconnect it). The label on the in-cab end of the PCM should have that code as well.

Is this a California truck, by any chance?

 

so there is no ecm but there is two pcms? It is not a California truck.

 

There's only one PCM.

 

I wonder if the mechanic swapped the IDMs and not the PCMs
The IDM is at the drivers side fender. The PCM is on the drivers side at the lower portion of the firewall. May want to verify which one he changed

 

That's what I'm thinking too.

 

That would be an epic oooooops......

 

I was posting on a thread "manual to auto tranny swap" I was under the impression that the IDM and PCM had to be changed together, but after we discussed it awhile, and doing some research we came to the conclusion that the IDM's are all interchangeable, though send a different amount of volts.

I assume the different voltage will open the injectors farther the higher the volts, but I dont know how big of a deal that would be for him unless it was a lower voltage IDM starving it for fuel???

Sorry about the hijack of this, but I would like to be better suited to answer questions like these.