Expert: Ben Deutschman - 9/2/2010

Question
I have a 64 Dodge Dart with a 225 engine and AT.  It starts and runs fine,
however, when it comes to a stop, the engine dies.  It restarts immediately and
runs fine until another stop.  Several mechanics have worked on it and none can
find the cause.  The carburetor has been rebuilt.  Thanks for any help.

Answer
Other than a Carburetor related problem, the only other thing I can think of that would cause a stalling problem like your car has, would be a vacuum leak. As soon as the car would try to idle, the lean condition caused by the vacuum leak, would cause the car to stall out. The leak could be between any one of the Intake Runners and the Cylinder Head, due to a rotted out Gasket. There could also be a crack in the Vacuum line coming from the Distributor to the Carburetor. If you Dart uses Vacuum Servos in the Vent/Heater Ducts, a leak there could also cause the problem you described. The Intake/Exhaust Gasket problem may be diagnosed by carefully, and I do mean carefully, spraying Carburetor Cleaner around the area where each Intake Runner meets the Cylinder Head. Keep in mind that the Exhaust Runners are right next to each Intake Runner, and Carb Cleaner is flammable. The Distributor Vacuum Line is an easy experiment, just run a new one. The Rubber Line is cheap enough, and with a small sample piece, easily enough matched up to new material. If you have a Vacuum Line off one of the back Intake Runners, that runs in through the Firewall, then you have Vacuum Servos controlling the Flaps in the Heater/Defroster Ducts, and simply capping the Fitting at the Intake, and taking a test drive, would eliminate, or pinpoint the source of the problem, which could be the Vacuum Line leaking.  If it isn't the Line, then in a Heater system using Vacuum Servos, one of the Servos could be at fault, and you'd have to unplug, and temporarily plug the Line at each Servo, until you found the bad one. G-d knows where you could find a replacement for the bad Servo.