Q: Sounds and acts like car is out of gas, but it's not. on 1991 Lincoln Mark VII

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After driving in city traffic for about an hour the car dies usually at a red light or stop sign. Sounds just like it is out of gas but it cant be because I put in plenty of gas when I started driving. So I add about a gallon out of my portable gas tank and everything is fine again. The car is running very cool as I have a new radiator. When I add that gallon of gas after my car dies it seems like it loosens up a possible blockage. Could this be a fuel filter problem or could my fuel injection be bad. Thanks for your help. dko
(1) Answer
(1) Comments
It does not sound like a fuel filter, because that would give you symptoms no matter how much fuel was in the tank. This problem could be many things, ignition coil, fuel pump or plugged exhaust. You need to have fuel pressure, delivery volume, the presence of good spark all checked at the time of the symptoms. Good luck.
It occured to me that maybe it is not the gas I add to the tank that solves the problem, but it could be when
I remove the gas cap, air or vapor is released allowing the engine to start again.If that is the case what is causing my vapor lock.

Thanks a lot,