Strange Starting issue on 1980 Jimmy

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Marcos

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I have a 1980 GMC Jimmy that im having some minor issues with but its driving me crazy. Jimmy runs great!, everything works the only thing is that if you turn the key to start it nothing happens. The trick to starting it is you have to apply slight pressure on the shifter on the steering column to do so. I thought maybe the issue was the adjustment on the ignition switch. Ive tried adjusting both directions even replaced the ignition switch but still having the same issue. I haven't tore into the steering column as im trying to avoid doing so but will if need be. Any help or suggestions would be greatly appreciated
 

gotyourgoat

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Possible neutral safety switch issue.
Have you tried shifting through the gears and attempting to start in each gear?
 

Marcos

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I haven’t tried that, I’ll give it a try when I get home. I did consider the n/s switch but I couldn’t find one on this jimmy
 

Matt69olds

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It’s on top of the column, near the floorboard. You should see 2 two wire connectors, one with a yellow and purple wire (the yellow is power from the ignition switch in the crank position, the purple is power to the starter “S” terminal on the solenoid), the other is blue (I think) and a light green. Those are for the reverse lamps. The light green is the power feed to the reverse bulbs.
 

Goldie Driver

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2 little 1/4 or 5/16 screws with bolt style heads holding it to the column on older models - at some point they went with one that you could move on plastic ratchets.

That style you can slide all the way clockwise after the shifter is in low and when you shift back to park it self adjusts .

I will guess the change was around 84, but hopefully they did it earlier .

Pretty easy adjust either way - just a tad difficult to get to those bolts.

IIRC on the bolt style you adjust it for the neutral position and the rest lines up.

Good luck !

Britt
 

Marcos

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Ok I tried starting in all positions other than park and nothing happened. Also tried adjusting the neutral safety switch but that didn’t fix it either.

Was also wondering if the linkage to the transmission may possibly be a culprit? Thinking of tightening it up a little

This area on the column has a little bit of play in it. Is there an easy way to get inside and tighten up some things without tearing the steering wheel off and key cylinder

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Matt69olds

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Do you have a test light? Disable the ignition, put the test light point on the purple wire. Hold the key in the crank position, and slowly move the shifter thru it’s complete range of motion. Hopefully you find 2 places that cause the test light to light up. If not, try the other wire. It should light the test light regardless of the shifter position. If not, you have an ignition switch issue
 

Marcos

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I do have a test light, ill check tonight. Its weird tho because I already replaced the Ignition Switch. Is it possible I bought a defective one?
 

highdesertrange

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" Its weird tho because I already replaced the Ignition Switch"

no it's not weird with todays junk Chinese parts. that's why I always recommend to do correct diagnoses
and just throw parts at it willy nilly. you very well could be throwing out a superior part that was good for an inferior piece of crap. highdesertranger
 

Marcos

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Hmmm ok tried the test light and didn’t get any lights to light up on the tester but I’m gonna try again when I have someone to assist. It’s kinda hard to use the test light turn the key and shift the column all at the same time. If all else fails I guess I’ll try another ignition switch or possibly try the original one
 

highdesertrange

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this is exactly what I am talking about.

before you just throw another ignition switch on there test it first. hell if the new one does the same as the original that means the original is probably good. if anything put the original back in and return the other.

then test your neutral safety switch and don't replace it unless you can confirm its bad.

you got to do proper diagnoses or else your are just wasting money putting junk parts on making you truck less reliable over the long run.

in the shop manuals you can find the proper diagnostic flow charts. it's easy to do it right.

highdesertranger

edit in my post #9 I meant to say "do not throw parts in willy nilly"
 

Marcos

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I get what your saying but both the ignition switch and the neutral safety switch must be operable if I’m able to get it to start right? Possibly out of adjustment? I’ve tried adjusting the switch and it either makes it worse or the same as before. It seems like there is an area in the column that isn’t making full contact only when I apply pressure on the shifter. I’ll keep messing with it. It’s quite frustrating tho
 

Marcos

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so I tightened up the linkage to the transmission which eliminated the play in the column and also made a huge difference when turning the ignition. Most of the time it starts right up if anything It just needs very slight pressure on the shifter to get it started now
 

highdesertrange

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did you adjust the neutral safety switch according to a factory manual? by reading this whole thread it seems that has been the problem all along. highdesertranger
 

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