Ignition coil ballast resistor location????
#16
02-15-2007, 12:01 PM
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Originally Posted by 90F250351
i checked for power at the coil with a test light and both terminals on the end of the coil have power. is that right?
The Dark Green/Yellow stripe wire is the tach test wire. It should pulse power only. Not be full power on.
Check the Dark Green/Yellow wire for a short to ground somewhere.
What I think is happening by your discription, is the dark green/yellow wire is shorted to ground, or you have a defective ignition module, and it is keeping the coil colapsed and keeping it from building a charge, therefore no spark.
Under normal operation the coil gets power from the Red/Green wire which is 7 volts in run. This voltage is stored and multiplied by the coil until it reaches around 10,000 volts. When the Ignition module gets a signal from the distributor, it sends a pulse through the Dark Green/Yellow wire telling the coil to fire. If your truck is equipped with a tach, the tach reads the pulse as well to figure out how fast the engine rpm is.
hope this helps...
#17
02-15-2007, 12:01 PM
Originally Posted by 81-F-150-Explorer
Look at and in the distributor itself.
Duraspark II distributors will have a "cog wheel" inside with 8 teeth. And you will see the magnetic pickup assymbly, will also have wires going to it. Ignition Module is located on the fender, and is independant of any computer control. Will also have a vacuum advance on the side. Most common before 1984.
Duraspark III distributors, they have no guts. They are just a rotor inside and some alignment screws. No wires going to the distributor at all. No vacuum advance. Ignition Module is located on the fender, and is dependant on the EEC-III computer system for control. Also has the CP sensor. Most comon on V8s in california before 1984.
TFI-IV distributors, the rectangular ignition module is located directly on the outside and bolted to the distributor. Dependant on the EEC-IV computer for control. Most common on trucks 1984 and up.
hope this helps...
Duraspark II distributors will have a "cog wheel" inside with 8 teeth. And you will see the magnetic pickup assymbly, will also have wires going to it. Ignition Module is located on the fender, and is independant of any computer control. Will also have a vacuum advance on the side. Most common before 1984.
Duraspark III distributors, they have no guts. They are just a rotor inside and some alignment screws. No wires going to the distributor at all. No vacuum advance. Ignition Module is located on the fender, and is dependant on the EEC-III computer system for control. Also has the CP sensor. Most comon on V8s in california before 1984.
TFI-IV distributors, the rectangular ignition module is located directly on the outside and bolted to the distributor. Dependant on the EEC-IV computer for control. Most common on trucks 1984 and up.
hope this helps...
Last edited by 82F1507.5; 02-15-2007 at 12:07 PM.
#20
02-16-2007, 03:56 PM
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No, because you wouldnt have power to the Red/Green wire at the coil.
Find out why you have power at the Dark Green/Yellow wire at the coil all the time. it should only have a pulse from the ignition module. Every time the dark green/yellow wire pulses, it fires the coil, with it full on, your coil will never fire, cause it's charge is always colapsed.
Check the Dark green/yellow wire between the coil and the module. I bet it's shorted to ground somewhere.
You may have to remove the wiring harness from the engine and completely unwrap the black protective coating to find the problem.
Invest in a good multimeter, and check the resistance of all the wires and connectors on the ignition wiring harness. If the resistance in the wires is greater than 5% then fix the wiring etc... (resistance wires excluded etc...)
Check the ignition wires too. Perhaps the coil wire to the distributor is broke... etc...
You have replaced everything except for checking the wiring. You should In my opinion always check wiring first.
good luck...
Find out why you have power at the Dark Green/Yellow wire at the coil all the time. it should only have a pulse from the ignition module. Every time the dark green/yellow wire pulses, it fires the coil, with it full on, your coil will never fire, cause it's charge is always colapsed.
Check the Dark green/yellow wire between the coil and the module. I bet it's shorted to ground somewhere.
You may have to remove the wiring harness from the engine and completely unwrap the black protective coating to find the problem.
Invest in a good multimeter, and check the resistance of all the wires and connectors on the ignition wiring harness. If the resistance in the wires is greater than 5% then fix the wiring etc... (resistance wires excluded etc...)
Check the ignition wires too. Perhaps the coil wire to the distributor is broke... etc...
You have replaced everything except for checking the wiring. You should In my opinion always check wiring first.
good luck...
#21
02-20-2007, 11:09 AM
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another question...would a bad starter solenoid by any possible change stop me from getting spark out of the coil? i hear clicking (almost like an arcing sound) coming from the solenoid on the fire wall when the key is turned to the start position. also, it seems that i dont have any power coming out of the wires coming out of the distributor???
#22
02-20-2007, 11:54 AM
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No the starter solenoid has nothing to do with spark on these trucks.
They did in the past though, but not on ours.
As for power coming out of the distributor wires it shouldnt have any unless the truck is running.
You should not test the wires at the distributor, or the ignition module it is possible to damage them. You need to remove the wiring harness and check the wires of the harness like I described before.
They did in the past though, but not on ours.
As for power coming out of the distributor wires it shouldnt have any unless the truck is running.
You should not test the wires at the distributor, or the ignition module it is possible to damage them. You need to remove the wiring harness and check the wires of the harness like I described before.
#23
02-21-2007, 08:29 AM
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started looking through the engine wiring harness last night and think i may have found the problem and one of the connectors. it is on the passenger side of the engine compartment the sits on top of the wheel well. looks like a main wiring harness connector. when i unplugged it, it cut off all power to the truck. i plugged it back in and jiggled it around and saw a very faint spark in my spark tester so i unplugged it. the plug was crack and severly corroded. i started scraping off some of the corrosion and one of the copper fingers in the plug just fell off! guess i need to visit the junk yard now...does anyone think this could have been my problem?
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