[Devquan]

i have a manual gp switch for my 93 f250 idi non turbo, it wouldnt start and normally when i press the button the volts drop because the plugs are taking power, but it's not doing that anymore. Bought a new gp relay hoping that would fix it but still nothing and now when i turn on the ignition the the plugs just click. also the glow plugs are new too, they're only a few days old someone please help

 

[RI_90_F250_7.3]

Use this thread to check out your glow plug circuit. Very informative and helped me to diagnosis mine.

http://www.thedieselstop.com/forums/f30/gp-glow-plug-controller-system-basic-diagnostics-296211/

 

[oldrebuiltdodge]

You might have a manual switch, but if it is clicking, then you most likely have a controller as well. The clicking you hear is the relay turning on and off, cycling probably due to burned out glow plugs. Check the glow plugs, each one of them. Pull them out and check across the battery, or check them with an ohm meter either way check them. You will most likely find your trouble. The clicking is normal after about 15 seconds of the wait to start light being on. Sometimes longer or shorter depending on the outside temp., and engine temp.

 

[710 Burner]

Clicking when the engine is cold (ambient) is a pretty good indication the resistance at the glow plugs is wrong, either due to aging, or wrong glow plugs. The truck I just purchased was reading .7 ohms at each plug (new, installed by the PO) I bought new GPs that were reading .2-.3 ohms and it works perfect. Make sure they are correct.