New problem today, car won't shut off

73greengold

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After working through my fuse issue yesterday, I started the car today and the starter sounded like it didn't disengage fully and the car wouldn't shut off from the key. I had to use the battery quick disconnect to kill the car. Could it be the ignition swich? I don't have a tilt wheel column and haven't ever messed with the ignition. Any thoughts?

Marty

 

71fastback

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After working through my fuse issue yesterday, I started the car today and the starter sounded like it didn't disengage fully and the car wouldn't shut off from the key. I had to use the battery quick disconnect to kill the car. Could it be the ignition swich? I don't have a tilt wheel column and haven't ever messed with the ignition. Any thoughts?

Marty
I had a similar problem with my car not shutting off because of the way I wired up the ammeter gauge. Hopefully someone else will chime in who knows more about how the electrical works.

 

droptop73

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I did have an ignition switch short out. When the key was in the off position it was normal. As soon as it was turned to run or crank the starter would engage and not disengage until I pulled the energize (cranking) wire from the solenoid.

 

OLE PONY

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The same thing happened to my 73 Convertible back in the early 90's. If my memory is correct I believe it was the starter solonoid.

 

72fastback

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yes a stuck solenoid will do that it happened to me also.

 

73greengold

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yes a stuck solenoid will do that it happened to me also.
How do you know if it is a stuck solenoid or ignition switch? How can I check the solenoid?

 

whitesoc

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yes a stuck solenoid will do that it happened to me also.
How do you know if it is a stuck solenoid or ignition switch? How can I check the solenoid?
I had the same thing with my 73 convertible, I replaced the solenoid and the problem went away.

I started with the easiest thing to change and that was the solenoid.

 

73greengold

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yes a stuck solenoid will do that it happened to me also.
How do you know if it is a stuck solenoid or ignition switch? How can I check the solenoid?
I had the same thing with my 73 convertible, I replaced the solenoid and the problem went away.

I started with the easiest thing to change and that was the solenoid.
Good point Ken:D

 

71fastback

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I might be wrong but when the key is in the off position, you shouldnt read any voltage through the starter solenoid.

 

Mister 4x4

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If I'm not mistaken, one side will be hot - it's just a big relay, after all.

 

c9zx

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The most likely cause, as others have said, is the starting solenoid has "welded" the internal contacts closed. If the engine quit running when you disconnected the battery it is almost a certainty that it is the solenoid. Wire 16A, Red/Light green, supplies voltage to the coil when the ignition switch is in the START position. If the contacts in the solenoid don't open when the ignition switch is moved from the start position the coil will still have power when the key is moved to the off position. OK, you have awakened the electrical gremlins and they are not happy with you.;)

Chuck

 

73greengold

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The most likely cause, as others have said, is the starting solenoid has "welded" the internal contacts closed. If the engine quit running when you disconnected the battery it is almost a certainty that it is the solenoid. Wire 16A, Red/Light green, supplies voltage to the coil when the ignition switch is in the START position. If the contacts in the solenoid don't open when the ignition switch is moved from the start position the coil will still have power when the key is moved to the off position. OK, you have awakened the electrical gremlins and they are not happy with you.;)

Chuck
I guess it's better to have the electrical gremlins mad at you rather then the wife! At least I can fix them without going to jail:D

 
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c9zx

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The most likely cause, as others have said, is the starting solenoid has "welded" the internal contacts closed. If the engine quit running when you disconnected the battery it is almost a certainty that it is the solenoid. Wire 16A, Red/Light green, supplies voltage to the coil when the ignition switch is in the START position. If the contacts in the solenoid don't open when the ignition switch is moved from the start position the coil will still have power when the key is moved to the off position. OK, you have awakened the electrical gremlins and they are not happy with you.;)

Chuck
I guess it's better to have the electrical gremlins mad at you rather then the wife! At least I can fix them without going to jail:D
Since you live in Fort Leavenworth I understand the jail reference.:) Let us know if a new solenoid fixes the problem.

Chuck

 

Don65Stang

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The most likely cause, as others have said, is the starting solenoid has "welded" the internal contacts closed. If the engine quit running when you disconnected the battery it is almost a certainty that it is the solenoid. Wire 16A, Red/Light green, supplies voltage to the coil when the ignition switch is in the START position. If the contacts in the solenoid don't open when the ignition switch is moved from the start position the coil will still have power when the key is moved to the off position. OK, you have awakened the electrical gremlins and they are not happy with you.;)

Chuck
Seems like that's how I checked to see if my alternator worked when I was younger. If the key is still "on" & the battery is disconnected, the car would still run by using the alt as the power source. If the key is "off" & batt disconnected - would that cause the engine to shut off? I don't know...just speculating with a foggy memory of things I've done to my car back in the day.

 

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In thinking this through, you said it sounds like the starter didn't disengage.

There is no mistaking that sound when the starter stays engaged and the motor starts, it's loud and you will jump.

If the starter stays engaged after the key is turned back to run, it's the solenoid

If the car stays running with the key off it's something else. Probably ign. switch, but you were working on fuse issues.

Solenoid is just a relay switch to engage the starter. Power wire from Ign switch to the coil keeps the car running.

Pull off the coil wire and try cranking it, if the starter keeps cranking it's the solenoid.

Don

 

73greengold

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In thinking this through, you said it sounds like the starter didn't disengage.

There is no mistaking that sound when the starter stays engaged and the motor starts, it's loud and you will jump.

If the starter stays engaged after the key is turned back to run, it's the solenoid

If the car stays running with the key off it's something else. Probably ign. switch, but you were working on fuse issues.

Solenoid is just a relay switch to engage the starter. Power wire from Ign switch to the coil keeps the car running.

Pull off the coil wire and try cranking it, if the starter keeps cranking it's the solenoid.

Don
Don, your spot-on with the starter engaged sound, it had me jumping quicker then rockets impacting around me a few years ago! I'm off to pick up a new solenoid this morning, I'll give you guys the verdict later.

 

73greengold

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ok, tried the new solenoid and the car is still doing the same thing, starter won't disengage when key turned to the off position. I'm going to try the ignition module next. What is the easiest way to lower the column to get at the 2 bolts holding it on?

Answered my own question by unbolting the steering column, lowering enough to get the nuts off and disconnected the switch. Have to wait until tomorrow for a new switch at Advanced Auto. I tested the old switch by having someone turn the car over and checked for voltage at the "S" side of the solenoid connector and had nothing. I'm hoping that leads to a bad ignition switch. Good thing is that these parts are fairly cheap so far.

 
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c9zx

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Does the engine now quit when you turn the key to the off position? Or was I misunderstanding that the engine would not quit running. Is it just the starter staying engaged?

Chuck

 

73greengold

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Chuck, you had it right, car wouldn't shut off & starter wouldn't disengage

 
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