Glow plugs not clicking

Snowturtle

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Is it a problem if my glow plug controller doesn't start clicking after the WTS light goes off? It used to.The plugs seem to be working and the WTS light stays on for about 20 seconds. It's hard to tell if everything is as strong as it should be because it's a 30 year old diesel and it's winter in Colorado! Its plugged in at night when I'm home but not when I'm somewhere else. It often takes me a few cycles of glow plugs and cranking if it was cold and the truck wasn't plugged in. I don't know if I'm concerned about that - it used to be better, but it's an old truck, I probably can't expect perfection!
 

adamsanders

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My glowplugs click sometimes after the light, sometimes they don’t. I guess it’s temperature related but it always starts so I haven’t really checked into it. I don’t know hold cold we are talking in Colorado but I can start my truck with one cycle of the plugs with temperatures down in the teens. It definitely doesn’t like it and it’s very rough for about 30 seconds but it always starts. You can test the glowplugs individually with a meter, check around on here for procedure.
 

franklin2

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You can get it working like factory new if you want to mess with it. The first thing I would do is take each wire off each glowplug and lay them all aside. Then get a testlight and clip the alligator clip to the + terminal of the battery, and then touch the probe to each glowplug tip. The testlight should light for each one if it's good. No light means that glowplug is bad. One bad glowplug will mess up your controller and make it not glow correctly
 

Stu Bailey

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I second the glow plug check with the meter. It will provide you with a lot of comfort in your diagnosis of what is/could be wrong.

I read one of the safety concerns if you are taking the terminals off the plug heads for testing is just to make sure you don’t let it rest on bare metal and risk shorting the circuit. Something about energized wires touching metal making a spark and costing money…
 

thisisagreatuser

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Is the system designed such that you are meant to be cranking while the plugs are being energized and glowing? So you start cranking right after WTS turns off? Thats, after all, when my glow plug controller starts clicking (only after WTS turns off) Part of me wonders if I should instead be waiting till the controller is done doing its thing and the voltmeter is recovered to full steady votage.
 

franklin2

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Wait to Start means what it says. When the light goes out, turn the key and start the engine. The clicking is just the controller glowing the plugs a little bit more to keep the smoke down some after the engine starts to make the tree huggers feel a little better.
 
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