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It won't start again!

1181 Views 5 Replies 4 Participants Last post by  manley
Okay...this is a 69 Mach 1 351W/ 4 speed.

The car will start with the key in the "On" position if I jump the terminals on the solenoid, but I can't get it to do anything with by turning the key all the way.

When I first got the car, I had a wire under the hood pulled out where it runs into the fuse box on the other side of the firewall. I fixed that and the car started and ran and it was great! I don't know what happened, but when I put the car all back together to take it for it's first ride in 10 didn't work again.

The wire that I fixed is hot on both sides of the fire wall. The wires on the ignition switch are hot when they are supposed to be. When I turn the key to "On", both coil terminals are hot(are BOTH supposed to be?). All fuses are good. I have a new battery, alternator, starter, solenoid, voltage regulator...

Anyone have any clues? My first guess is that the ignition switch is bad. Could a bad solenoid cause this problem?

Anything else I should check?

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If it starts when you jump across the soleniod then the solenoid is no working.Does it click when you turn the key to start? Another hint that the solinoed is no good.
Your engine feed harness has three wires, one goes to the + side of the coil, one to the oil pressure sender and one to water temp. I do not have the book handy so cannot give you the colours. However I think if you replace your solenoid again it should start ok. If the wires still get hot after your replace it then you may have something shorting somewhere else that is causing this. But lets see if it will start on her own with the new solenoid first.
Hate to disagree with dcudmore, but if you can jump it across the selonoid to make it start, the selonoid is fine.

You've got either a bad ignition switch, or broken (or unplugged) ignition wire (red/blue one going to "S" post of terminal).

Check voltage between the red/blue wire that goes to selonoid and a known good ground with the key in the start position. My guess is you'll have no voltage.
IMHO you have a bad solenoid or ignition switch which exhibit simialr problem. your ignition ckt at start is 12V battery thru ignition switch, neutral safety switch (auto tran only, and to "S" terminal on solenoid. this 12 Vs picks up a relay in solenoid which in turn pulls a bar across terminals that are connected to battery on one side and starter on other side. when you "jump" the solenoid you are just shorting this switch out and applying 12 V directly to starter. if the 12 V does not get to "S" term you will not pull that relay up and you can still start by jumping solenoid.
to isolate which of these problems you have apply battery 12 V to "S" teminal with jumper wire ign key in "run" position - CAR IN NEUTRAL/PARK or NEUTRAL with e-brake on or your garage door may get hit.
if the 12 Vs on "S" terminal does not jpull up solenoid you have bad ign switch, bad neutral safety sw if auto tran., or wiring problem.
if you hear solenoid relay pickup (a click ) but starter does not turn , your solenoid switch is bad. thest typically faill when contacts inside get pitted from arcing when pulling hundreds of amps at start - especially in cold weather.
Sorry so long. PM me if questions
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On the solenoid, if you installed a new one it can be faulty. If you overtighten the connections it turns the inside and damages the contacts.Use 2 wrenches when you tightend the wires to prevent the inside from turning.
Everyones ideas are reasonable and worth a look, that is why this forum is so great. .Never thought of that neutral switch, It can even be corroded connections there, if you have an automatic.
I finally solved the problem after tearing my dash apart and tracing every wire...lots of thinking...lots of searching for bad wires.

The problem was created from my own ignorance, but let me tell you that I came away with another bit of knowledge.

I had the car running and I was cleaning up a few things under the hood that I didn't like. Well, my reverse light harness ends about halfway to the reverse switch and I didn't like having those wires just hanging there. Soooooo, I unplugged it from the connector at the firewall. I noticed the other wire that came out of plug and looped directly right back into the same plug, but didn't think much of it.

Guess what? That loop is apprently how you bypass the neutral safety switch when you use a manual shift car.

I was reading through past post and read about how Ford did it from the factory and a light bulb nearly exploded in my head.

I ran out and plugged the reverse light harness back in and fired the car up!

Thanks for the help guys! I don't know what I would do without the VMF!!!!!
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