Anyone have Rochester quad stalling at cold temperature?

Example: drive up to a stop sign after cold start, throw the gear in neutral and engine dies out. It just started happening and it's annoying. I have to warm up the car at least 5 minutes before heading out.

I thought it was vacumm leak but can't find any leak at this time and choke plate is 1/8th inch from closed.

** scratching head **

Thanks

 

More details on engine. Stock or modified, how if so.

 

modified. 406 ci roller. base idle is around 700 rpm when warmed up. fast idle was set to 1200 rpm but during 1st minute of cold start, fast idle is jumping between 1200 rpm high all the way to 500 rpm low.

thanks

 

Could be a vacuum leak or maybe it needs a little less than 1/8" choke when cold and running.

Has it ever run OK cold? It's OK in Park but dies in Neutral?

 

When standing in neutral from cold start, it does not die. It dies if I come off gear throw in neutral and coast in to stop sign. I also suspect vacuum.

I will look further into the vacuum anomalies. I do have to give throttle to pop open the headlights also so vacuum at low idle is a suspect at this time.

Thanks for the reply.