I have been dealing with a hunting idle and dying, then having to restart on each cold start of my 740 Turbo. If I start it and pull it into gear and take off it seems to do just fine.

It will high idle for maybe 10-15 seconds, then dip and die. If I give it gas it typically stays running, but can hunt a little once I let off. After as little as a minute of running it stops hunting. If it dies on the first try it almost never dies on the second try.

Also, I typically have troubles with any kind of start in extreme cold. Not saying this is related, but it could be.

I have replaced all sensors a few years ago trying to fix this. Perhaps one of the replacements was bad. Also, this is an engine I rebuilt, so it has been in and out of the car a few times. I could have missed a ground or something I suppose.

 

check all the air plumbing between the MAF and the throttle body.

make sure the throttle body isn't gummed up

make sure the idle switch on the throttle body closes (0 ohms) when at idle, and opens (infinite ohms) when its just a hair off idle.

make sure the rubber hoses under the throttle body to the Idle Air Controller (IAC) are intact and not cracked, make sure the IAC is not gummed up, and that its electrical connector is clean and connected..