Engine in fail safe mode. Could someone help?

[350Zweden]

My throttle valve actuator works slowly and opens only 20% at full throttle according to an OBD2 simple scantool. 0-100 in 14sec. Seems to be in fail safe mode. It’s a 2005 with A/T.

A friend tested with an OBDpro that says ECU BCM IPDM ABS TCM are ok. The only thing that does not seem ok is the closed throttle position sensor that says NG. Don’t know what NG means. (not going?) With ignition on signal to position sensors are ok but apparently not when driving. I've measured all outputs from ECU (76st) with a multimeter and an oscilloscope. Seems ok. Tested with  2 different ECU, 2 different Throttlevalves, 2 different IPDM and measured the Can system that is ok. The mistake I think occurred when  the previous owners took power thieves and  shortcutted the harness. Therefore, I have also changed the Engine Control harness but the error remains. I bought the 350Z cheap knowing  that it was in fail safe mode.
There are no error codes (then it would be easy) A very skilled Nissan master tec tested with consult 2 for 2 hours but did not find anything wrong. He says all sensors and computers seems ok and “talk” to each other’s. Previous owner tried to install nitrous gas and shortcutted wires..His plan was that the positions sensors should activate the gas to be injected. The A/T was also in safe mode but I solved it by changing the TCM in the gearbox .
Not much hope that someone could tell me whats wrong but I give it a try. You could be my hero!!! Jan from Sweden

[andybp]

try this 

[350Zweden]

Thanks Andy. Resetting the ecu to relearn idling and so on ive done. Problem is that throttle valve is in failsafe mode (signal from ECU). But without any fault code.   

[aceves]

Did you find the fix for the problem? I'm currently having the same issue with the throttle only opening between 12 and 20% even at WOT. Any knowledge would be highly appreciated.