Neutral safety switch dies when warm

[73 Plymouth Duster]

So I am having problems with my Duster dying due to fuel issues (another whole topic on here) but the bigger problem is when I can't get it started at a light because the neutral safety switch wont "engage" after going from park to neutral and wiggling the shifter around (on my 727) I can eventually get it to start (wort time was 30 sec until I got it)

When I got home to diagnose my other fuel problem I tried to start it after about 5 min once I had turned it off and it fired no problem. I shut it off and tried it in neutral and no problem. Looked under the car the wires look good, it was plugged in tight so I am assuming I can just go throw another switch in my tranny? Is this a common way they fail?

Thanks in advance!

 

[cudajim]

You could have a bad transmission switch, bad wiring, bad relay or most likely a misalignment of your NSS switch. I'd start by pulling the NSS wire off the relay and grounding it with a jumper, see if it starts in any gear. If so your switch is either bad or misaligned. It's supposed to switch to ground when in neutral or park.

 

[FredS]

probably alignment. These switches usually don't fail.

 

[67Dart273]

You could have a bad transmission switch, bad wiring, bad relay or most likely a misalignment of your NSS switch. I'd start by pulling the NSS wire off the relay and grounding it with a jumper, see if it starts in any gear. If so your switch is either bad or misaligned. It's supposed to switch to ground when in neutral or park.

Yup.......could be any of the above. You can eliminate the switch.................get a clip lead and hook to the MIDDLE terminal of the NS switch, bring it out to a test lamp on the battery. Now you can wiggle the shifter and see what it does.

If the lamp does not light reliably in park or neutral, but DOES light when you carefully "wiggle" past those, then it's probably linkage adjustment. Should be a sliding adjustment under there

If it DOES light OK in park or neutral, it's in the connector, wiring, relay, or maybe the start signal from the key is the problem. This start wire goes through the bulkhead connector, so could be suspect.

If it lights OK in park / neutral, time to check the wiring and relay. Pull the wire off the start relay (the quck connect which goes down the firewall to the transmission) and ground that relay terminal with a clip lead.

Start the car several times CAREFUL it will now START IN ANY GEAR so be darn sure its in park or neutral!!!!

If it starts reliably several times, the relay and start circuit are most probably OK, and it's a bad connection in that wire to the trans or most likely the NSS connector at the trans.

ALSO not sure about your car, along about 73/ 74 "they" had that stupid seat belt interlock reset. Look under the hood for the reset. IF IT'S THERE cut the two "yellowish" wires and wire them permanently together

Here:

http://www.forabodiesonly.com/mopar/showthread.php?p=1969624169

http://www.forabodiesonly.com/mopar/showthread.php?t=14304

 

[73 Plymouth Duster]

Okay, I suspect it is probably at the plug, I have really nice and tucked away exhaust that it runs by. I put head shield around it but since it only has issues when the car is hot Ill play around with it thanks!

 

[RedFish]

Both the dying and the not restarting could have the same root cause, ignition switch and/or connections.