David,

ALL 123 cars have vacuum door locks. They work by simply locking the drivers door and all the doors, the trunk and the fuel tank door will lock, providing, of course, that they are working correctly. Since you obviously have a vacuum leak keeping the shut off from working, the same lack of vacuum prevents your door locks from working as well.

jcd's trick for quick and dirty testing is a good one. Lock the drivers door and see if the engine will then shut down. You will have to hook the system back up the way it was before you created the "suck tube" for the test.

Let us know the outcome and we will lead you to the problem. Or drive it to Cedar Hill park in the Dallas area on Novemeber 17 and we will gang up on it and find the problem.

Have a great day,