Troubleshooting No Idle

[rustyruststang5]

My car is a 1988 mustang aod, 306, hci, bang turbo kit, pmas mass air blow threw.
So this weekend I swapped out my aod this weekend for a better one. now i start the car to fill the aod it idles fine i notice the ps head gasket it leaking antifreeze. so then i swap out the head gasket. i get the car all back together and it idles ok, but not perfect. so i turn it off and go grab my timing light, now i go to try and start my car and it will not start.... it ended up being a bad coil(wtf) ok so i swap it out.
so now where i am at is the car will start up and just die right away. if you help it with gas it will stay running. so I had someone keep it running while i set the timing at 10 with the spout out. then it just dies after they let off the gas. So then I decide to take the car around the block and see how it acts. and going around the block in gear it act perfectly normal (I didn’t get on it) but at stop signs it idles fine drives smooth, I get it back in the drive way and put it in park and it just dies. Does anyone have a idea of what it could be? Could the neutral safety switch on the Trans have anything to do with it? Because I just left the one on that came with the new transmission. Any other thoughts or ideas? I was thinking vacuum leak until I went around the block and it acted fine but I might see if I can get ahold of a smoke machine to be sure. But I am stumped

 

[7991LXnSHO]

We could guess a long time on this as many things as you has to touch to do all that work. Did you go through the Surging Idle list?

As far as the neutral safety switch, that should allow it to start or not and is tied into the starter circuit only. If it allows the starter to work in P and N but not in gear, it passes my check.

 

[jrichker]

You guys with idle/stall problems could save a lot of time chasing your tails if you would go through the Surging Idle Checklist. Over 50 different people contributed information to it. The first two posts have all the fixes, and steps through the how to find and fix your idle problems without spending a lot of time and money. I continue to update it as more people post fixes or ask questions. You can post questions to that sticky and have your name and idle problem recognized. The guys with original problems and fixes get their posts added to the main fix.

It's free, I don't get anything for the use of it except knowing I helped a fellow Mustang enthusiast with his car. At last check, it had more than 134,000 hits, which indicates it does help fix idle problems quickly and inexpensively.