Hey, I’m no stranger to my ‘91, I’ve owned it since ‘95. I recently replaced all the glow plugs and a new controller. Shortly afterward the GPC quit and the relay appears overheated. Installed all new GPC with relay. It cycles on, WTS light goes out, but then it continues to power the plugs. Not the afterglow cycling, it just stays energized for another 5-7 seconds. It does this no matter the temp, and no matter how warm the engine is. Never any normal cycling or clicking of the relay. All wires checked, ground checked, and I’ve searched the forums for this issue.

 

What brand glow plugs do you have installed?

 

They’re suppose to be the motor crafts or Beru. Shop installed as the previous shop used auto light so I had them pulled.

 

Errr. Ill pull the easiest one to access and take a look a the name on the side of it. These Glowplug systems dont like anything except motorcraft/beru.

 

I will, just to make sure. I’ve experienced all the usual GP and GP controller issues but this one’s just odd. Heats up and starts fine, but I know it will cause issues running them that long constantly on instead of cycling.