1991 7.3 IDI will only start off solinoid

Markoriginalowner

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New neutral, safety switch new ignition switch new solenoid under hood still only starts by jumping the solenoid. All in line fuses are good under hood by battery. Saw a guy at getting gas and he did the same thing same year truck must be a common problem. Anybody have any ideas?
 

ihc1470

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Start checking voltage from the key switch out. Bad connection or broken wire in the start circuit is about all it could be.
 

IDIBRONCO

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We'll need a little more info here. What year? Do you have a tilt steering wheel? Is the neutral safety switch adjusted properly (will it start in neutral but not park)? It could also be along the lines that ihc1470 mentioned.
 

IDIBOBS

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Gonna have to have atleast a voltage meter if not a power probe. Makes life 1000xs easier and faster. If you apply power to the start peg then n the start solenoid under the hood does it run the starter.
 

Brian VT

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I'm in the same boat. When I turn the key I get a solid noise like you'd get with a low battery but no start. Same in Park or Neutral. I replaced the contacts board in the column. No luck. I gave up and rigged a push button start.
 

Rdnck84_03

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I have 4 bullnose trucksand have had the same issue on 2 of them.

I had to run a new wire from the switch to the solenoid on my 83 6.9. I believe that the wire was broken somewhere, it is routed in a hard place to access so I just opted to run a new wire. It has been in place for a couple years without a no start situation since

I currently have the neutral safety switch jumpered on my 84 F-150, I installed a new NSS and adjusted correctly but it would still not start sometimes. The jumper has been in place for almost as long as the wire replacement on the 83 and haven't had a no start since. I believe that the new switch was bad out of the box but not sure.

James
 

Brian VT

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I had to run a new wire from the switch to the solenoid on my 83 6.9. I believe that the wire was broken somewhere, it is routed in a hard place to access so I just opted to run a new wire.
What switch does the wire to the solenoid come from? You are able to use the key to start after replacing it?
 

IDIBRONCO

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I just opted to run a new wire.
Thje bonus here is that you bypass the clutch switch this way. Personally, I don't like those and bypass them whenever I can on my own vehicles.
What switch does the wire to the solenoid come from? You are able to use the key to start after replacing it?
I comes from the bundle of wires that attach to the ignition switch (not the key switch) on the lower steering column. IIRC there's only one that has power ONLY with the key in the start position. That's the one that you want.
 

Rdnck84_03

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What switch does the wire to the solenoid come from? You are able to use the key to start after replacing it?
As @IDIBRONCO said, it is the ignition switch on the lower part of the steering column. I searched trying to find the post I made with pictures and the switch pin number. Unfortunately I don't remember how long ago it was or if I made a thread or posted it in the "what did you do with your truck today ".


Thje bonus here is that you bypass the clutch switch this way. Personally, I don't like those and bypass them whenever I can on my own vehicles.
I believe that the clutch switch became standard in 84, my 83 didn't have it anyway.

James
 

Rdnck84_03

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Finally got tired of the "will it start with the key or am I going to have to roll to flat ground somewhere so I can just the solenoid" !

I have been chasing this issue for over a year and this is the first time I have actually had it still present when I got it in the shop to figure it out. Somewhere in the starter solenoid wire is a short to ground but I couldn't find it, so I ran a new wire.

This isn't the fix I wanted but the issue usually only happened when you really needed it to start with the key, like in a really busy gas station parking lot with sloped parking.

James
I finally found it. I didn't post the pin call out like I thought I did. The picture does show the wire color, I'm not sure if the color is the same between 83 and 91 thought.

I will see if I can find the screen shot of the switch pin out on my phone that I used when I did it. 80 through 91 use the same switch so the pin out will be correct regardless of wire color.

James
 
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