Having a problem starting the car. It acts like the automatic choke just is not trying to kick in. When I first go to start the car it will turn over but I have to rev engine using the accelerator or RPMs drop and it stalls. If I rev engine for a little while 5min+ the choke kicks in then and RPMS stay at about 1000. Once I put it in drive RPMs stay up and it stays running. Never stays once it is in drive. Any Ideas ?