I have a 95 F350 with the 7.3 engine but the glow plugs aren't working. I put a test light on the glow plug relay and the test light stays on with the key on/engine off but when starting the light flashes on and off and was wondering if this is normal. The WTS light works like it should and all the glow plugs have been replaced as have the harnesses. Also when the engine starts the battery voltage right away which it never did before. I'm not experienced with diesels so I have no clue if my relay could be bad of its something else. Anyone have any suggestions?
yes, sounds like the GPR (relay) is the last culprit in your system. you can test for voltage drop across the terminals with key on. i am sure you will get more help from the lads here. i think it should not be much more than .1 volts drop. if all the other stuff is new and working and hooked up , get a new relay, search that too as some are junk. Good luck! oh and as glow plugs go on the older trucks and aging sensors etc etc, if its pretty cold........always helps to wait another 4-10 seconds after the light goes out before cranking, the plugs stay lit generating more heat.
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1995 F-250 PSD 4X4 EXTRACAB LONG BOX AUTO
TYMAR FILTER, 4" MBRP STAINLESS TURBO TO TAIL
EOT MOD FOR COLD STARTS
CUSTOM RUNNING BOARDS
SD STARTER
STANDENS FULL 3 LEAF FRONT SPRINGS
1990 25th Anniversary 5.0 GT
You really can't test the relay with just a test light, you need a digital volt/ohm meter. There should be less than 0.3v difference between the two large lugs with the key on and the relay energized. Anything more and it is a bad relay.
You also need the digital meter to test the glow plugs since you are only looking at tenths of a ohm for a good plug vrs a bad plug.
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96 F250 PS XLT 4X4 long box, 5sp,4.10, manual hubs,pyro+boost guages, Dark Toumaline, add a leaf, Dale's TYMAR, and HX hose, downpipe, coolant filter, Luk clutch
There's not much to the system, if the relay is not bad and 12v are going to the plugs, the harness is not burned and the plugs are not burned open, then the plugs are working. Plugs are for all intents and purposes simply a light bulb. They get volts, 12v, they light, they heat. They don't get 12v they don't light. They get 12v, but are no good they don't light. That's pretty much all there is there to worry about.
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1997 F350CC, 4x4, PSD Tipper pro kleenex open filter. Roggen 6" lift kit with 26" ratflex 12" offset tires. Downpipe cut and welded to adapt 3" into a 12" outlet. 12" muffler cut and adapted to 2", then a special turbo manifold from a volkswagon modified to flank out to 3" to the tail pipe. Interior from a Corvair modified by cutting 6" off the padding. Snize and snide 32gallon aux tank mounted in rear seat, rear seat relocated to bed. Bed shortened to 4ft.
flicker or pulse, nope, don't thinks so, it stays full power to the plugs for up to 2.5 minutes or so, you can see the draw on the volt meter after you start, and then it go off completely and the volt meter jumps back up, and all you other lights come back to life............
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1995 F-250 PSD 4X4 EXTRACAB LONG BOX AUTO
TYMAR FILTER, 4" MBRP STAINLESS TURBO TO TAIL
EOT MOD FOR COLD STARTS
CUSTOM RUNNING BOARDS
SD STARTER
STANDENS FULL 3 LEAF FRONT SPRINGS
1990 25th Anniversary 5.0 GT
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