Its not the crank sensor.

[SELLSZ06]

My 98 Cobra has been acting up, it doesnt start at times and sometimes it does. I thought it was a crankshaft sensor, put in one new it did nothing different. I take the fuel cap off the fuel rail and sometimes it has preasure sometimes not, fuel pump maybe? I have one ordered but Iam not sure that is the problem, also the theft light on the cluster flashes, could this be related to the car not firing up sometimes? Help please.

 

[RippinSVT]

Check the PATS system. It's the computer-system that controls Anti-Theft and the chip in your key.

 

[STAMPEDE3]

Fuel pump relay sticking. is another possibility