[mlach1127]

Hi all,
New guy here from Massachusetts.
Quick backstory on the 65. Picked it up for my dad last father's day. We drove it a decent amount, and ultimately parked it due to just about everything leaking and it overheated. June 1 2019, I pulled the drivetrain. Rebuilt the engine, resealed the transmission, and fixed the overheating issue with a 3 row aluminum radiator, 6 blade fan, clutch, shroud, and a 180* tstat. I'll save the rest of the details for another thread.

Here's the issue: Got the Mustang back together. Went to fire it up for the first time since the rebuild, and it would only start in neutral. The NSS switch was new. Looked through the service manual and saw a few threads on here that there is an adjustment. I went ahead and followed the procedure, and got the car to fire up in park (and of course neutral). Fast forward a couple days. I had a couple leaks I needed to address before making our maiden voyage. Went around the block a few times, then headed back home. Once home, I let the car idle in the driveway for a bit. While putting some tools away, I heard the car shut off. Odd. Went to see what happen, and couldn't find anything obvious. Went to start again, nothing. Moved the shifter down to 1, then back to park. Turned the key. It fired up. This happened a few other times since. I replaced the ignition switched. Started the car a handful of times with no issues. I thought I was all set. I dropped the Mustang off for an alignment Tuesday morning. Got the call that the car was all set to be picked up. The guy told me he had an issue starting it a couple times, and it died on him once pulled out of the garage. I told him I was aware of the issue. While trying to drive the car home, it shut off on me 5 times in the parking lot. While in gear. Would not start in park, only in neutral. My question is: could the NSS still need adjustment? Causing the car to quit while in gear? Is the ignition switch faulty? Or do I have a bigger issue. **Engine temperature doesn't seem to make a difference, as it shows the same symptoms whether the car is hot or cold. Electrical isn't my favorite, but there can't be much to these switches in my opinion.

Thanks in advance for the help!

 

[Matter]

Your nss will only affect starting and would not cause the car to shut off as it is only part of the starting circuit. Possibly 2 seperate issues or may be related. Possibly a loose connection somewhere causing the car to die, with the car running try wiggling wiring in areas that seem suspect and see if it will die. Seems more than coincidental that when it dies it goes back to not starting in park. See if perhaps the shifter is moving any wiring when put in park, like maybe it moves the harness and opens a bad connection somewhere?

 

[mlach1127]

I will give everything another once over. I thought the coil may be bad, but that was also brand new. Anything is possible. The other thing I just thought of, was that when we bought the car, the brown wire off the starter solenoid was not connected. Since reassembling, I went ahead and hooked the brown wire back up.

 

[Magnus]

The brown wire just gives you 12v to the coil when cranking the engine. So it's nice to have but not having it won't cut the engine off (unless it grounds out).

While you're performing your advanced Ford Wiggle Test on everything make sure all your grounds are good too.

 

[Flade]

Sounds like a loose wire or ground. Check the wires at the coil. Unfortunately these days just because a par5 is new doesn’t
mean it’s good. There are endless stories here of brand new offshore parts that were bad or failed within days/minutes of install.

When it fails or won’t start, confirm if it is a fuel issue (do you get a good squirt of fuel when you press the accelerator?) or an ignition issue. (Pull a plug wire and check for spark). That will help you narrow it down.

 

[Hemikiller]

Sounds like a loose wire or ground. Check the wires at the coil. Unfortunately these days just because a par5 is new doesn’t
mean it’s good. There are endless stories here of brand new offshore parts that were bad or failed within days/minutes of install.

When it fails or won’t start, confirm if it is a fuel issue (do you get a good squirt of fuel when you press the accelerator?) or an ignition issue. (Pull a plug wire and check for spark). That will help you narrow it down.

Agreed.

Verify you have solid battery to chassis and engine to chassis grounds.