From what I've read, there are some really smart guys here when it comes to these 7.3 trucks. And I'm pulling my hair out here. I'd appreciate any help you guys can give. Told a friend from work I'd look at his truck. He said it would momentarily cut out every now and then, sometimes just die. At an idle, driving down the street, and it would pretty much always start back up. He also said he's put 8 batteries in it in 2 years. So, he brings it over, I start doing checks once I see it happen.
When it cuts out momentarily, the check engine light, WTS light, Water in Fuel light all come on. Now, I made a stupid assumption that the WTS light comes on when the PCM is first powered up. And I realize he was putting batteries in it so often because every time it glitched or cut out, it would begin the glow plug cycle over. So, between that and the WTS light, and the fact it will sometimes lose power on the control side of the IDM relay, I assumed the PCM must be resetting.
He wanted to just put a PCM in it, so he got one. That didn't fix it. I pulled wiring diagrams and module pin out info. I found 3 power feeds and 3 grounds for the PCM. Every ground can carry the load of a bright 5amp light, and none of the power feeds are losing voltage when it happens, but it will occasionally cut out and decide to turn off the IDM relay.
I don't know these trucks, I don't usually work on diesels much. I'm about to tell him that he needs to take it to someone more familiar with diesels than me, but my pride is really fighting that one.
Thanks in advance for any help.
It did set a few codes, I'll include them.
When it cuts out momentarily, the check engine light, WTS light, Water in Fuel light all come on. Now, I made a stupid assumption that the WTS light comes on when the PCM is first powered up. And I realize he was putting batteries in it so often because every time it glitched or cut out, it would begin the glow plug cycle over. So, between that and the WTS light, and the fact it will sometimes lose power on the control side of the IDM relay, I assumed the PCM must be resetting.
He wanted to just put a PCM in it, so he got one. That didn't fix it. I pulled wiring diagrams and module pin out info. I found 3 power feeds and 3 grounds for the PCM. Every ground can carry the load of a bright 5amp light, and none of the power feeds are losing voltage when it happens, but it will occasionally cut out and decide to turn off the IDM relay.
I don't know these trucks, I don't usually work on diesels much. I'm about to tell him that he needs to take it to someone more familiar with diesels than me, but my pride is really fighting that one.
Thanks in advance for any help.
It did set a few codes, I'll include them.