my 1996 cobra will not start. it cranks good but doesn't even try to start. I got it to start once after holding my foot down on the gas pedal. after it started this way I could rev it but after letting off the gas it quickly dropped in rpms and died. I just got back from a 2400 mile round trip and it might of got bad gas in it, so I will change out the fuel filter first. any other thoughts on what to check? I might be able to hook my a fuel pressure gauge I have sitting around.