I just installed an EGR delete tube and for the 4 days my truck sat apperently everything is going bad.
After installing tube went for test drive truck won't get out of it's own way check eng light on bunch of codes.
Next day double checked to see if I forgot something couldn't dind anything that I know of only 2 plugs hanging are EGR and Intake Air Heater but found some wires chewed under fuse box after further diagnosis.
Fixed them all codes gone except one P0090 Fuel Pressure Regulator circuit malfunction. Got a tech 2 and hooked up followed GM DTC flowchart as follows:
Step 1 Perform DTC check ANSWER YES go to step 2
Step 2 Key on eng off is FPR commanded % above 20% AWNSER NO go to step 20
Step 20 Replace ECM
Is it possible my ECM died while sitting in my driveway or am I overlooking something.
My mods are in my signature any help would be appreciated.
Thanks Guys in advance

Mike

How much is the ECM? If anything try to buy one from a junk yard one but you have to stay with monkeying around with those bad wires. Hope you didn't solder them. I used to repair very sensitive electronics besides being and Electrical engineer. Solder isn't really for creating a good connection but for making a connection mechanically sound. On circuit boards it is used for obvious reasons but actually has been replaced by wire tracing. In earlier days we didn't have the machines to do good wire tracing so solder traces were used. That created two problems, impedance problems and cold solder joint problems. Glad we have evolved!!!!!

If it were me last resort would be to buy a new ECM. I don't fear the cost of it as much as fear that it doesn't fix your problem.

Nope didn't solder them was affraid that if i put heat shrink on the wire would get hot and melt heat shrink before i could slide it and i didn't have much to work with so went with butt connectors with glue always had good luck with them.
I agree it's not often that an ECM goes bad (far as I know) so don't know if I need to supply power or ground to something because of the 2 plugs I have hanging or what .
Truck sat for 4 days can't believe all this can happen like that worked as a GM tech for years (unfortunately never got to work on diesels) and never really heard of all this going wrong from sitting. Don't know????
Anyone seen anything like this. Tomorrow I'm gonna try to get my hands on the wiring schematics for this circuit but not sure if that will help since ECM isn't even commanding anything?

Anyone??? Is there something I can check or am I just putting an ECM in and would you trust a used one off ebay that has been tested or would you get new
Thanks
Mike

Anyone??? Is there something I can check or am I just putting an ECM in and would you trust a used one off ebay that has been tested or would you get new
Thanks
Mike

I would rather go to a junkyard than get one off ebay. Either way you don't know if they have been tampered with but I would think the junk yard would be cheaper.

I think I priced one a while back. I think the dealer said they wanted something like $600 for a new one.

ok gonna do a few more checks I have a buddy works at a dealer might be able to get me a decent price I'll post back with results

I just installed an EGR delete tube and for the 4 days my truck sat apperently everything is going bad.
After installing tube went for test drive truck won't get out of it's own way check eng light on bunch of codes.
Next day double checked to see if I forgot something couldn't dind anything that I know of only 2 plugs hanging are EGR and Intake Air Heater but found some wires chewed under fuse box after further diagnosis.
Fixed them all codes gone except one P0090 Fuel Pressure Regulator circuit malfunction. Got a tech 2 and hooked up followed GM DTC flowchart as follows:
Step 1 Perform DTC check ANSWER YES go to step 2
Step 2 Key on eng off is FPR commanded % above 20% AWNSER NO go to step 20
Step 20 Replace ECM
Is it possible my ECM died while sitting in my driveway or am I overlooking something.
My mods are in my signature any help would be appreciated.
Thanks Guys in advance

Mike

Those flowcharts almost always take you down the wrong path.

No broken wires to the pressure regulator? Is it plugged in?