Surgeing & Glowplug Problems Today

[icanfixall]

While driving today everything was warmed up and running fine. Then the truck surged as I was in second gear twice. I tried to make it happen the rest of the drive but not happening. I switched tanks but nothing. The injection pump has about 7 thousand miles on it and its the 5070 pump. I run plenty of Stanadyne in every tank. So the second problem was when I got home I herd the glow plug controller clicking on and off like it was a cold start up. The coolant temp was 190 degrees. So what is the collective thoughts on whats going on....

 

[Agnem]

Loose ignition circuit maybe? A momentary power lapse will initiate a GPC startup sequence. A longer one might seem like surging.

 

[icanfixall]

Thanks for the answer. But what causes the controller to turn on and what tells it to turn off after the motor warms up? Am I looking for a temp sensor?

 

[towcat]

gary-
check your connections to the GPC. A voltage interruption will trigger it to cycle. I am wondering if the surging is caused by the cold idle circuit kicking in too.

 

[2manydsls]

Read Mel's second sentence again. If you turn the key off and on real fast it could cause the problems you describe. You may be looking for a loose or corroded electrical connection. Problems that come and go are the hardest to find. Good luck.
Ross

 

[icanfixall]

I have this new controller FOTZ-12B533-A.... Is this a solid state controller for my 89 7.3 motor?

 

[Agnem]

You could always run a temporary wire to your IP connected to a light bulb in the cab. If you see the light flicker at all, even the slightest bit, you found your problem.

 

[icanfixall]

If I decide to disconnect the glow plug controller which wire do I remove? I can always start it and then disable it do I don't run the risk of burnning up the plugs and then dropping a tip in the motor.....

 

[typ4]

Check the big connector at the passenger fender to the engine.

 

[icanfixall]

I installed the controller I posted a question about. The solid state one I removed showed signs of heat damage on the underside at the brite shiny capasators or what ever they are called. Gees... It had almost 300,000 miles on it. Didn't owe me anything. Easy replacement too.