I don't really know what to do...HELP!!!
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I don't really know what to do...HELP!!!
My boyfriend has a 75 f100 302 stock A. Just the other day, we tried to get it started after letting it sit for a couple of days, and it started fine, and we went to the grocery store, and when we went to leave, the thing wouldn't fire over. It sounded like it was more inclined to start when you turned the key off, then when it was supposed to. After letting it sit for a while, it finnaly started, we got about 25 miles, then it just quit, and refuses to start, it turns over fine, but only starts when you let it sit for a while, and don't plan to take it too far. It will just shut off like I turned the key off. I replaced the coil, and the ignition module, which have been tested and are supposedly fine, but this sounds like an electrical problem ,and I am at a loss!! Help!!!
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I don't really know what to do...HELP!!!
I replaced the coil, and the ignition module, which have been tested and are supposedly fine, but this sounds like an electrical problem ,and I am at a loss!! Help!!!
sounds like something is getting hot, did you replace the ignition module or just check it? if you just checked it and you are not duplicating the hot conditions it will pass it's test. I say it is your ignition module that is going bad.
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I don't really know what to do...HELP!!!
Since it sounds like it wants to start when you release the key to run, I would say the problem is in the start circuit. There is a wire from the ignition relay, "I" terminal, to the coil ( actually to a splice behind the dash first), that puts 12 volts direct to coil for startup. The wire could be bad or the igniton relay could be dying.
The splice I mentioned has the wire from the starter relay meeting the wire from the ignition switch then another wire contiues to the coil. The starter relay wire has 12 volts for starting, the wire from the ignition switch is actually a resistor wire and drops the voltage to 8volts or so for running, and of course the other wire is just a path to the coil + .
If you have a points style distributor this is most likely the problem. However if you have a dursspark module, it could also be the module suffering from "heatstroke"
If you have a voltmeter check for 12 volys at the "I" terminal of the starter relay when you have the key turned to start, no voltage = dead relay. If you have voltage, remove the wire from the + of the coil and check for 12 volts when the key is turned to start. Voltage at the relay and none at the coil = bad wire.
Hope this helps.
Sparky
The splice I mentioned has the wire from the starter relay meeting the wire from the ignition switch then another wire contiues to the coil. The starter relay wire has 12 volts for starting, the wire from the ignition switch is actually a resistor wire and drops the voltage to 8volts or so for running, and of course the other wire is just a path to the coil + .
If you have a points style distributor this is most likely the problem. However if you have a dursspark module, it could also be the module suffering from "heatstroke"
If you have a voltmeter check for 12 volys at the "I" terminal of the starter relay when you have the key turned to start, no voltage = dead relay. If you have voltage, remove the wire from the + of the coil and check for 12 volts when the key is turned to start. Voltage at the relay and none at the coil = bad wire.
Hope this helps.
Sparky
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I don't really know what to do...HELP!!!
Thank you for the help. When my boyfriend tested some stuff on the truck, he found out that the truck doesn't have points, and not only that he is getting intermittent spark when the motor is turning over, I hope that helps. I will try what you guys said, and again, thanks for the help, I will keep you updated.
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I don't really know what to do...HELP!!!
[font size="1" color="#FF0000"]LAST EDITED ON 14-Aug-01 AT 10:20 PM (EST)[/font][p]I don't know if they had it back in '75, but take a look inside the distributor. Is there a spikey gear-like wheel? If so, is there a thing that looks like an electromagnet by the wheel, that has lots of tiny wire wound on it?
If so, that sounds like a Duraspark II setup. If it is, the pickup is the thing with the wire on it. Disconnect the pickup connector just outside the distributor. Look at the color code of the wires to the connector and the pickup. With a DVM, should measure some resistance from the connector, through the pickup, and back to the connector. Don't get mixed up with the third wire, which is a ground.
Thes pickups have been known to open up over time, over temperature, etc. but usually work for years no trouble. An open pickup will not start when cranking, but will fire when the key is just turned off.
And oddly enough, if you do get it started by luck, it may run fine with a small break inside the pickup coils wire! But when you shut it off, its back to luck again.
If so, that sounds like a Duraspark II setup. If it is, the pickup is the thing with the wire on it. Disconnect the pickup connector just outside the distributor. Look at the color code of the wires to the connector and the pickup. With a DVM, should measure some resistance from the connector, through the pickup, and back to the connector. Don't get mixed up with the third wire, which is a ground.
Thes pickups have been known to open up over time, over temperature, etc. but usually work for years no trouble. An open pickup will not start when cranking, but will fire when the key is just turned off.
And oddly enough, if you do get it started by luck, it may run fine with a small break inside the pickup coils wire! But when you shut it off, its back to luck again.
