Join Date: Dec 2008
Location: Tyler, TX
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I would suspect that the GPR (Glow Plug Relay) is not working correctly. When the GPR gets worn out, not enough voltage can make it to the glow plugs, and consequently, they do not get hot enough for the engine to start.
You can verify this by measuring the voltage ACCROSS the two LARGER GPR terminals with the "Wait to Start Lamp" on. Your reading MUST be lower than 0.5Vdc (1/2 volt), if it is more than that, the GPR is BAD.
'93 F-250 HD, 7.3L IDI, 5spd - FARM TRUCK
I Support: Trailer brakes an every axle over the towing vehicle's GVW; CDLs for RVers; Safety inspections for ALL vehicles and 6 axle trucks (97K GVW proposal).
Democracy is two wolves and a lamb voting on what to have for lunch. Liberty is a well-armed lamb contesting the vote - Benjamin Franklin
I vote for LIBERTY!