Hello!
I am new to the diesel world and recently picked up an 85 6.9L F250. Odometer and previous owner say 66k miles, general wear agrees, but with rollover at at 100k who really knows. Either way it's old and WA rain doesn't help.
IT starts up without any issues and runs well. But the last few times I've started it I have noticed the glow plug light on the dash comes on for 1 second, off for 5, and repeats 3-4 times during warm up. After that it doesn't come on while driving and I have no issues. Is this a sign of one or more glow plugs needing to be replaced? Thanks!
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nope. that means the glow plugs are coming on for a second or two after startup to help the engine warm up.
it is normal on the 87 and newer solid state glow plug controller.
only difference is the newer ones do not turn the glow plug light on for that second.