have fuel, no spark

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fueler4506

Junior Member
Joined
Jun 4, 2016
Posts
4
Reaction score
0
Location
Eagan, MN
Ram Year
1988
Engine
3.9L
I just got an old forestry truck the other day. 1988 D-150 2wd short bed. It has the 3.9L w/ a 4 spd. When I towed her home, she had no fuel and no spark. After digging into it, I found the wiring harness to the pump was pinched between the bed and tank, split and melted all four wires. Honestly, with the burn marks under there, this shoulda burnt to the ground. So, thats fixed. Pump hums and builds pressure. Now I still don'have spark. The boob that was working on this installed a bunch of new parts(throw everything at the wall, see what sticks) new plugs, wires, cap, rotor, coil, throttle body, injectors and T.P.S. The the resistor looks old and there is no reciept in the truck for it. When I attach a multimeter to the wires(seperated and attached to the coil) both tests and both wires, when the key is turned to the "on" position, hit with-in a volt or two of what the battery is at amd almost immediatly drop down to .1 volt. Ive scanned a bunch of the harness and found no more melted or broken wires. What was damages has been repaired properly. They had the resistor hooked to the negative side of the coil. Im nearly 100% sure its supposed to be on the positive side. Anyone out here have any knowledge on where to look now? The truck has 60k original miles on it, came from Montana and is in REDICULOUSLY good shape. If push comes to shove, ill dump in a carb'd 318 and call it a day, but this thing is WAY to nice to cut up. Not to mention, there is the whole... pride... thing, in losing a battle against, what I can only assume, to be a wiring issue. HELP HELP HELP HELP HELP
 

crazzywolfie

Senior Member
Joined
Apr 6, 2013
Posts
16,431
Reaction score
3,192
Location
under the truck
Ram Year
81 93
Engine
5.2
seeing voltage at the coil for only a second after turning the key on is normal. the computer only turn the ASD relay on for a few seconds to prime the fuel system then shuts it down again until the computer senses that you are cranking the engine and trying to start it.
 
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