Today, while driving home, the GP light on my car came on, shut off, and then randomly came on for a short time, then stayed on for a few minutes.
It shut off before I parked the car.

It does operate properly at initial start up. The GP's test at 7 ohms and are Bosch.

Any ideas?

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RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

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I wouldn't stress it too much. Mine did that once, after hitting a big bump. Never did it again.

I'd be more worried if it kept it up. Then I'd suspect the relay.

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1979 300D 040 Black on Black - 1985 300D Maaco job (sadly sprayed over 199 Black Pearl Metallic) on Palamino

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See if the screws that hold down the Fuse are tight and if the Fuse itself has a crack in in it.

Get out your Mtilmeter (volt ohm meter) and turn the dial to 200 ohms. Take the 2 probes and put them together. If you get a reading as I do mine (you are reading the resistance in the wires of the probes) you need to subtract that from the what you get when you check the Glow Plugs.
If you have a quality meter when you put the probe together you will likely get zero.

This is not a recommendation to by parts from Disel Giant but he has how to test the Glow Plugs and he is showing an uncorrected reading of 00.9 and 00.8 ohms.

When I just checked 2 new made in France bosch 80006 Glow Plugs I got uncorrected 00.8 ohms from both of them. If I subtract the resistance of the probe wires I get 00.5 ohms.
This is what you said you got; "The GP's test at 7 ohms and are Bosch."

Another problem can be like the pic. The Glow Plug Ohms were OK but the Glow Plug is supposed to get hottest at the tip not in the middle. So that is a bad Glow Plug even though the Ohms were OK.

Attached Thumbnails

 

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84 300D, 82 Volvo 244Gl Diesel

Had the same issue a couple years back on my 83 300D. Turned out to be the glow plug relay. I'm betting it is the same problem with yours.

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