This has happened about 4 times now. I will be sitting in my car for maybe an hour and then when i turn the car on the THEFT light is flashing and the car wont start. I have to get out and unplug the battery for ten minutes and let the computer reset.

anyone else have this issue?

 

The THEFT light will "blink out" diagnostic codes if the PATS has been able to determine the problem, here is how to interpret the patterns:

 

Is the car sitting out in the sun or is it only happen on warm days?

 

Its definatly pats related.

 

The transponders in the keys do get weak, it is not at all common but it does happen. If the encapsulation of the chip is at all compromised moisture and crap can get in and create capacitive pathways that "short out" the RF signal...

 

its only happened while ive sat in the car with the key in the ignition but car off. Today was the first time it did it while the car had been parked at work for 9 hours. its snowed today.

 

Have you determined if the THEFT lamp is blinking out a trouble code?

 

I am not sure how to read that chart because my engine will start but then dies because the fuel line is cut off (i assume) so it will start for 1 second and die. The light flashes rapidly when the key is in the on position.

 

Your 1997 GT has the PATS type A system which uses a stand-alone PATS module and sometimes the THEFT lamp does not blink a diagnostic code, though Ford says it should--I have yet to find out why.

I have very little information about that system however I would suggest you get a new key (any good local locksmith can make and program one) as that is the most likely cause of intermittent starting issues such as you describe.