Very Cold Start with Starting Fluid spray can

[Coug]

it won't necessarily go to 0V after the battery voltage.
They have what's called afterglow. Basically help the cylinder heat up a little quicker.
Some do it by pulsing the glow plugs every couple seconds for a minute, some do it with reduced voltage.
Either way, voltage should be either under about 12V or should come and go in pulses, but not remain at battery voltage past 9 seconds.

Not sure your knowledge on how to actually use the meter, but here is a quick video that explains measuring resistance.

 

[Tiwaz]

Thanks a lot for the video explanation, luckily I am very comfortable using oscilloscopes, multi-meters and any measuring device related to electronics. I just did not know how to measure a glow plug not having seen one ever but I guess is as simple as: ground on the thread and + on the center pin and expect between 2-4 Ω ?
My main question though is what is the correct step sequence to start troubleshooting, What is the very first thing you should check...?

 

[Coug]

Thanks a lot for the video explanation, luckily I am very comfortable using oscilloscopes, multi-meters and any measuring device related to electronics. I just did not know how to measure a glow plug not having seen one ever but I guess is as simple as: ground on the thread and + on the center pin and expect between 2-4 Ω ?
My main question though is what is the correct step sequence to start troubleshooting, What is the very first thing you should check...?

Yes, one end on contact tip, other on threads or if installed in engine any engine ground will work. As there is no diode or anything, just straight resistance, it doesn't matter which meter lead goes where.

First check the glow plugs for continuity.
If every single glow plug tests bad, you need to test to make sure the voltage to them is correct and turns off when it's supposed to.

That is a little less important if you still have a couple of glow plugs that are usable, as that means the controller is probably turning off voltage when it is supposed to (smaller chance that you have bad wires to only those good glow plugs and all the rest are getting fried)


For plug uninstalled, one on the threads or body, and the other at the small tip where the electrical wires connect.

1.5 to 5 ohms is considered good.

Glow plug testing with pictures halfway down this page, borrowed a couple of the pictures for here.

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Good plug test

Bad plug