O/D Light Flashing & Low Power

[jvest]

I recently purchased a 2002 F450 with a 7.3 PS & auto tranny. I drove it over 400 miles to get it home with no problems. After installing a utility bed on it I've noticed it losing power momentarily. It may last a few seconds or several minutes. I don’t have a boost gauge, but it seems like its losing boost. It still runs, but just under powered. I can kick it up in neutral, turn the key off and start it back and the problem is gone. During this power lose the O/D light is blinking. I read some posts where the blinking O/D lights were caused of tranny issues, but the tranny is shifting fine and no slippage. Any help would be greatly appreciated.

Thanks,
Jim

[jvest]

I pulled codes today and got the following.

P0380
P1105
P1106
P1747

Any advise would be greatly appreciated.

Jim

[Fireman40]

I have never pulled codes on my truck. I dont have a reader so I can't help you here. But I have had the o/d light flash before and two week later my torque converter blew up. I have also had it flash the the truck ran very weird. Almost like i had it in low gear. it was extremely responsive and very jumpy. It turned out to be bad fuel. However you say you installed a work body. Is it possible that you may have pinch or kinked a fuel line? then when you turn the truck off and back on the fuel pumps boost your fuel pressure back up

[ryansjake]

Originally Posted by jvest

I pulled codes today and got the following.

P0380
P1105
P1106
P1747

Any advise would be greatly appreciated.

Jim

This is what I've gotten so far from reading Shopkey5 about your trucks codes.

P0380 - Glow Plug Circuit Malfunction
- Open or Grounded Circuit, Solenoid Open or Shorted, Failed PCM. Have to get in there and start looking around, a wiring diagram would do wonders to help.

P1105 - Upper Generator Fault Detected
P1106 - Lower Generator Fault Detected
- Possible blown fusible links between batteries and Generator(s) (Alternators), Possible open in power or ground to Generators, Faulty Generator(s) or Faulty PCM

P1747 - EPC Solenoid Circuit Shorted or PCM
This is where your Flashing OD/Off light will be coming from. The Electronic Pressure Control soleniod circuit in the Transmission is shorted to ground or power, or the PCM has gone crazy.

I do know that the plugs for the trannys are crap, and can break and have water enter them and cause issues. I'm still being lazy and haven't replaced mine yet. But it does happen.

So from what I've seen, this seems to be 3 different problems occurring at once. Does it start fine with the glow plugs, charging gauge ok and battery light not on while running, and trans shifts ok?

Without being physically able to see or diagnose your truck in person, I'm kinda suspecting the computer is starting to go crazy. Those 3 things are not too related, but still, it should be looked at by somebody who has access to proper testing techniques.

Hope this gives you some direction!

[jvest]

ryansjack, good info. After clearing the code and put a few days on the truck, we pulled the codes again and got P1105, P1747 & P0380. I beleive I do have a bad glow plug and is hard to start because of that. I've got a replacement, but have not had a chance to do it. I'm not sure about the upper alternator fault, but check the fuselink you mentioned above. The battery light is not coming on, but not sure if that means much. When the O/D light flashing the transmission is shifting hard and the engine is low on power. This issue does seem to get a lot better once the truck warms up after 10 to 15 miles of driving. Since it's gotten colder the last couple of days it has gotten worse. There some corrosion on one of the pins on the main transmission harness, but after cleaning it didn't help.

Jim