chetmus

The dealer replaced the TPS and thought the problem was solved. Two days later, boom, failsafe mode again.

The dealer has now installed a triggerable data recorder in the car. The next time it happens, I'm to press a button on the device to start it recording what is going on with the car at the time.

One thing I found is that my local dealer is "not fond" of "internet solutions".

Mustangs197gt

[QUOTE=TorchRedBeauty;1031431]There are any number of reasons for the car to go into fail-safe mode. The torque issue mentioned is only one of them. My car went into fail-safe mode before I put any mods on my car because of a faulty throttle position sensor (TPS). In this case, the car went into fail-safe mode because it wasn't getting as much information as it needed. Since it was only receiving information from one of the two throttle positions sensors, it didn't think it had a reliable signal and went into fail-safe mode to protect the engine. When in fail-safe mode, the engine will run extra rich, have extreme throttle lag and (I think?) run on only 4 cylinders. It runs like a dog, but it's for the safety of the engine. Bring the car in with the light on and the dealer will be able to read the code(s). If it is the TPS, it's a quick fix.

Hey I'm having a similar problem on my 05 mustang gt and the problem I'm having is hanging rpm and at idle the car will differ from 1200 rpm to 600 and almost stalling. I tried replacing the tps mounted on the throttle body and it fit loose causing it to mess up more but still waiting back I believe It was a faulty part but you mentioned there is two tps sensors, do you know where I can find the other sensor? And any suggestions as to what else it might be, thanks,
Brian



05 mustang gt
62mm bbk throttle body
K&N intake
39lb injectors
Off road x
4" muffler
Hurst short