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Posted

When I did the AFM & DOD hardware ware delete, I sent my ECM to Texas Speed for tuning. When I installed the computer, and after starting the truck it ran fine, but the dash was showing engine reduce power, traction and stability control off, service power system, and service a/c system. After looking everything over, I did realize that I forgot the main ground coming from the battery that mounts to the cylinder head, (WTF moment). After several attempts I could not get the truck to start. It would turn over but would not start. A good friend of mine is a CAT mechanic and he brought over his scanner and it pulled codes: p0102 (MAF), p0107 (MAP- New sensor), p03040 (CMP - New sensor), p0452 (FTP), p0522 (EOP - New Sensor, no filter), p0532 (a/c), & p0641 ( 5 Volt Ref 1 Circuit). He cleared the codes and then the truck would start. Idles beautifully. But the dash was still showing the same messages, and the codes reappeared.

 

I sent the computer back to Texas Speed. He looked it over and said the bench test and tune was good. He said he disabled the VATS and put the computer in a similar truck and the ECU wouldn't do anything. The ignition would turn on, but the starter wouldn't even turn over. He mentioned that it could still be the VATS that is not letting truck turn over. He had another guy look at it and bench test it, he even said he thinks my ECU is good. I asked him to check the volt reference, not sure if he is or is going to. He is now planning on ordering me a refurb ecu, flashing and tuning it and then sending back to me.

 

My truck has been put back together and ready for about 2-3 weeks now. I have traced my harnesses, and checked my plugs. I have not had any indications of broken, smashed wires or broken plugs. No blown fuses.

 

 Is it possible that I may have bricked or damage my ECM by not having the main ground connected? There is also a ground wire that connects from the battery to the firewall, and the ecm is ground thru the cab. right?

 

Trying to get some ideas of what my problem is before I haul this in to my local Chevy Dealership.

Posted

Sorry guys for not listing my truck info in my original post.

 

2007 Chevrolet 1500

LTZ Z71 4x4

New Body Style 

Vin: 2GCEK13Y971553459

186k miles

  • 4 weeks later...
Posted

Turned out my cam sensor wiring was pinched/ frayed. Bad coolant sensor, and oil pressure sensor as well as the tune on the ecu from TSP was a little off. 

 

Truck runs smooth now. 

  • 8 months later...
  • 2 years later...

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