[wrenchspinner3]

I'm cross posting over from the Team Shelby site hoping for more ideas here:
Last night my 2009 GT500 went into 'Fail Safe Mode' after coming in off a 40 minute trip on the highway. The 'check engine' light did not come on and I don't believe the engine temperature gauge was even at the halfway mark. I limped home, shut her off for about 10 minutes and then all seemed Ok. Coming into work this morning it went into 'Fail Safe Mode' again. Shut her off immediately and restarted after 5 minutes. It then seemed OK again. The engine temperature gauge was below halfway again. The outside ambient temperature was about 70 degrees, so not even hot weather. The only mod on the car are KR mufflers, put on about 500KMs ago. The car now has 5,000KMs on her. Anybody have any ideas as to what might be going on? I was just getting ready to have the FRPP cold air intake and Pro Cal installed shortly too! It's at the dealership now, but they can't find the cause. They say there is no overheating situation, but the car thinks there is one, so it goes into Fail Safe Mode

 

[wrenchspinner3]

...Well got the car back. The part replaced was a fuel tank pressure sensor which is located in a small hose off the fuel tank. Part of the EVAP System I imagine. When the tech could make the car go into fail safe mode, the codes retrieved where: P012C, P0192, P0405, P0452, P0642, P1000 and P1227. Ford knew of some cases where the 5V V-ref circuit internal to the sensor would short. I would imagine then, that the 5 volt circuit to all these other sensors, indicated by the trouble codes, lost thier 5 volt supply as well. It's still a guess, as PIN tests did not show any problem. Hate this intermittant stuff! I have about 30 KM's on the car now, as well as the tech's test drive, with no problem so far. The FRPP cold air kit has been installed too. Can't say I notice a big difference in performance yet, but then I haven't really put the boots to her yet. Thanks for everyone's help.

 

[ssgviper]

glad u got the car back hopefully that was the fix i think you have a computer program concern,maybe flashing with the ford racing program will help,i noticed an improvement with my ford racing cai kit and the blower is noiser also which i like