Riflemanusmc

Check every ground on your rig. Chassis/Cab/battery.. Buff them off, spray them with a good coating...Every ground you can find, redo them....

1-5-3-6-2-4

thats borderline insanity. we do enough of them to keep a spare ddec V ecm loaded with the test spec on the reprograming station cart. but man thats unbelievable.

do you ever profile the warrantee numbers you get there with a national average? is it geographic location related

1-5-3-6-2-4

the ecm grounds directly to the batteries. the 5 pin power harness - takes voltage fused directly to the battery. Pins A & C are positive Pins B, D, & E are negative.

Heres a trick to testing the power harness. you need to draw a load through it. what I mean is. its very possible that you put your trusty multi meter on it and pin out source voltage through pin A&C and you have continuity through the grounds. but rig up a cheapo 12v tractor light with some wire and pins. and put a lead to any known good ground. and pin it to A&C. if doesn't light full boat. through both. you might want to mess around trying to find the high resistance. or the wire might be green right through. replace the power harness. I beleive they are not expensive. it has a 2pin that jumps from the power harness to the vehicle interface harness for ignition trigger.

bigdave

That is a very good idea. I have had those situations before where a meter said that it was ok but it really wasn't. In fact, the power wire going to the lift pump on my pickup was that way.

Riflemanusmc

That problem child truck was in the shop almost two years ago. IT is why DD has changed it up. Trust me. Going by DD's wr rules. We were to the breaking point on this FL. Couple of turbo's. Lots of senders and trouble shooting times. Two flashed ECM's. One engine harness. FL and DD were back crawling on this rig..

Riflemanusmc

Check your CHASSIS ground. Nothing to do with the batteries..

Albernikid

Working on an older FL with series 60 dd. The ECM main ground was under the glove box passengers side. It was throwing a bucket load of unrelated codes before i found the poor ground. A little green looking around the stud but not loose. Up and hauling since then. Another issue I ran into with it was worn out pin connectors on the ECM sensor harness, tied the harness off to one side and the problem went away. Have to replace the connector ends in the harness when I get time. Gr8 discussion guys.

Skip H

Since the truck works fine when the motor is heated up a little- I would suspect a coolant sensor.
Seen a lot of these bad over the years.
JYHO

DiezelSmoke

These engines have vary few problems with electronics. If it isn't throwing codes go back to the basics. The 2 most common problems with low/lower than normal power is fuel supply or turbo boost. Make sure you have proper fuel pressure and proper flow. This could be as simple as a fuel filter or harder such as deteriorated fuel lines, fuel pump, etc. Check turbo boost pressure it should be close to 26-28lbs. of pressure under load. If it isn't you have an air leak, intake gaskets, the most common is the red or green hoses on the pressure side of the intake, usually you will get a woshing sound or muffled wistle similar to to a standard turbo whislte. Next most leak is an after cooler, they are just like a radiator, ends of the core usually leak, take it out and pressure test it.