My comet has run in to a problem that has got me stumped. The car will start fine and drive for about five minutes, if it has been sitting for about three hours, but than it will sputter and die and will be impossible to restart for the next five, or more, minutes. When it restarts it will either run for about two seconds or it will run for about three minutes tops. At first I assumed it was water in the gas tank, but when I aded gas dryer and filled the tank the problem did not change. In addition if I turn off the car rather than let it die it will still not restart. In all cases I tried to restart the car both with and without starter fluid and it made no real difference. The carburetor, battery, and starter solenoid are all new and functional, and the alternator is also working. We have not adjusted the carb from the factory specs. It does not appear to be a fuel problem, I can blow through the fuel filter. Could it be an intermittent spark problem, if so how could I test for that, and where should I look for the source?
Dieing/not starting when hot is almost always a ignition issue(loss of spark), the Duraspark electronic modules are famed for this problem...
I had a problem with my engine dying randomly and everyone said it was the Duraspark box. I replaced the box and it didn't fix the problem. I changed the Duraspark ignition system to Pertronix and still had the same problem with the engine randomly dying. I replaced the ignition switch and it fixed the problem. I had the same dying issues with my Falcon and traced the problem back to a bad starter solenoid.
Fuel tank venting OK? Cause if it's plugged, the pump won't pull fuel against a vacuum. You could try running it temporarily with a rag for a cap...
definitely sounds like the ignition system is over heating and cutting out. all the above ignition stuff is possible. you can either shot gun repair it by throwing parts at it, or test to find the problem. when it dies you need to disconnect the coil wire from the distributor cap and lay it on the intake or valve cover with some gap between the end and what ever its on and crank the motor to see if it sparks or not. most likely it wont. now you need to see if the duraspark box has power or not with the key on. if it does then most likely the duraspark box is the problem. if it doesnt then its a good chance its the ignition switch.
My second guess would be a plugged up sock in the tank. If the tank is rusty the particles build up on the sock as the pump draws fuel. When the engine shuts off the rust drops back into the bottom of the tank and it will run again. Had this happen on a Granada I once drove.
I'll check the ignition, and the starter. I replaced the duraspark box, and I tried replacing the coil, but so far the problem has not been solved. I'll also check to see if I'm getting any spark when it doesn't want to start.
