engine wont kill with key

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Chances are the ignition solenoid has gone bad and is allowing some voltage to flow to the I post - basically hot wiring the car. If it does it again, disconnect the I wire (usually the small one farthest from the battery). If the engine shuts off replace the solenoid with a Motorcraft replacement, not a chinese one.

 
Chances are the ignition solenoid has gone bad and is allowing some voltage to flow to the I post - basically hot wiring the car. If it does it again, disconnect the I wire (usually the small one farthest from the battery). If the engine shuts off replace the solenoid with a Motorcraft replacement, not a chinese one.
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This is good advice.

 
More to the story............I went out last night to check everything and found my battery was dead. Tried to charge it, but it wouldn't take a charge at all. So, went and got a new battery, and the car fired right up, but the tach was barely moving. So I tried to shut it off, and of course, the motor kills with the key!! WTH? Fired it back up and now the tach is working perfectly again. Oh, and when I hooked the new battery up I got a small spark from the positive post indicating a short somewhere, but after the tach started working again, I disconnected the battery and no more spark at the positive post, so whatever the draw is it affects the tach when its acting up. Could this all still be the solenoid? My solenoid is new. Cant remember the brand, but I want to say its not Chinese.

 
Omie01,

It would not hurt to take a look at the ignition switch located on the column. You could check to see if it is aligned per the Ford Specs. It also might be worn out, especially if it is the original one. One thing you could do, is swap it out with known good switch and see if you can reproduce the issue.

mustang7173

 
It's possible that when tightening the cables on the solenoid that the large terminal spins to make contact with another terminal within the solenoid. A back up wrench is recommended when securing the cables.

 
More to the story............I went out last night to check everything and found my battery was dead. Tried to charge it, but it wouldn't take a charge at all. So, went and got a new battery, and the car fired right up, but the tach was barely moving. So I tried to shut it off, and of course, the motor kills with the key!! WTH? Fired it back up and now the tach is working perfectly again. Oh, and when I hooked the new battery up I got a small spark from the positive post indicating a short somewhere, but after the tach started working again, I disconnected the battery and no more spark at the positive post, so whatever the draw is it affects the tach when its acting up. Could this all still be the solenoid? My solenoid is new. Cant remember the brand, but I want to say its not Chinese.
Click to expand...
The anything connected to the coil + side, including the tach would be powered on if the solenoid's I post was energized.

 
And that is why I always recommend to measure the current draw of the car before connecting the battery. How? Use a digital volt-ohm meter, set to DC amps. Connect one side of the battery (usually positive first), then one lead on the negative battery post and the other lead on the disconnected negative battery cable. Anything over 100 milliamps usually means something is on. Anything over 10 amps usually indicates a short somewhere. Most classics without a memory line for the radio reads 35 milliamps.

Be careful: most DVM's are fused at 10 or 20 amps DC, which would give a reading of 0 amps if the current was more than allowed.

 
Maybe she just wasn't ready to be put to bed? :D:D

 
Exact what Randy said.

Any reasonably cheap multimeter can also do amps ...

With the car dead, you should barely have a trickle.

If not, start by removing fuses until you isolate the issue.

I even have an original clock which I turn off (via a hidden switch) when not driving.

(It's always correct twice a day.... right?)

 
Thanks Midlife I will try that. I did replace the ignition switch last night anyways and everything seems to be back to normal. But I will still perform that test and get back to you!!! Thanks!!!

 

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