Tps Error Code, Weird Voltage Readings!

[clip14]

So I got my consult cable and checked out some of the free software on the net

car specs:

r32 skyline coupe

r32 rb25de ecu and loom (auto i believe)

r34 rb25de (swapped in, with manual gearbox)

error codes which showed up in consult:

TPS (throttle position sensor) error and automatic transmission something error

not too fussed about the AT error.

the TPS error however... checked the TPS voltage readings..

4.7V steady when throttle is closed (i.e. no foot on throttle). weird!!

then when i apply throttle, the voltage drops, with WOT showing a reading of around 2.0V

there is definitely something wrong here as it should show ~0.4v closed throttle and up to 4v open throttle.

does anyone have any advice or heard of this happening before????

[NewKleer]

sounds like tps wired backwards or something?

[clip14]

would it be as easy as switching the input/output wires of the tps?? i'm not sure how the tps measures the throttle position. maybe its the r34 tps which outputs differently?

ps. the cable is awesome nukleer

without it i would never have known my tps is acting up.

[NewKleer]

i imagine swapping wires 1 and 3 on the TPS sensor would do it (but id want to confirm that engine temp sensor, AFM, TPS switch etc are all operating correctly, otherwise it could be the wiring 'back up the line' more which is back to front).

given your bastard of a car with all the bits and pieces from here and there im surprised more isnt wrong

[clip14]

lol yeah it is a bit of a mongrel isnt it!!

I should really invest in a multimeter never was any good at electronics though.

I will take the tps sensor off tonight and see if any fiddling with the mechanicals will help. otherwise i suppose i will try switch some wires around :S

there are no other error codes coming up, afm voltages seem within normal range, engine temp readouts are around 80 degrees c when warmed up. so all the other outputs seem right. just the damn tps!

it explains the strange cutout thats happening when i apply 'wide open throttle'. must be the ecu being confused at the tps voltage dropping too low while airflow and engine speed is increasing.

I'm not sure what the previous owner did to the loom, so it is a bit annoying trying to track down other peoples dodgy mods.

[clip14]

I solved this problem (just then at 10pm at night in the dark outside with a torch held in my mouth)

car accelerates cleanly on full WOT from low rpm. seems stronger in the top end.

the plug to the tps has 3 pins

pin 1: one pin for the input of 5v

pin 2: the potentiometer output (triggered by the rotation of the throttle plate axle)

pin 3: and one pin for the output of the tps voltage to the ecu.

switch pin 1 and 3 and problem gone.

I still need to adjust the throttle pedal and cable as right now, when i push the accelerator to the floor I only reach 3/4 throttle ~3v

Edited March 30, 2009 by clip14

[NewKleer]

yep there you go

btw whats ur ecu serial nuber (23710-xxxxx?) and ill look up whether it is auto or not (i assume it is) on nissan fast program

[clip14]

yeah I think it's the factory auto ecu.

ecutalk shows this in the upper right hand corner when loaded:

ECU 08U11

Cheers

[NewKleer]

yeah 91/09-92/06 auto rb25de r32 ecu

[clip14]

cheers. any advantages of finding a manual ecu?

[NewKleer]

not sure