Autometer Wideband O2 Guage Installation

[Bitsushiti]

Hi guys,

I'm currently halfway through installing an Autometer (4378) Pro Lite Wideband O2 gauge in my Series 2 R33 GTST.

So far so good, I've got the gauge and o2 sensor installed but I'm a bit hesitant on continuing with the wiring for the peak/recall & warning function, which reads from the wide open throttle switch signal.

The instructions state:

"WOT Peak/Recall mode provides you with a quick and easy way to find out exactly how "lean" your engine got during the last pull, run, or race. This value is recorded when the Brown wire in the instrument harness is connected to a good engine ground via a normally open, momentarily closed wide open throttle switch. This allows peak readings to be sampled only during wide open throttle conditions. If the Air/Fuel monitor gauge will not be used with a wide open throttle switch, connect the brown wire permanently to a good engine ground to continuously monitor for peak conditions."

Can anyone confirm which wire this is on the ECU harness? I've had a look at an RB25 ECU pinout and there's two TPS wires, which are #38 = "Throttle Position Sensor Sense", and #48 = "Throttle Position Sensor", but I'm not confident in which one would be the WOT switch wire.

If anyone could point me in the right direction it'd be much appreciated

Cheers & thanks

[mad082]

neither is the WOT switch. they are both just TPS sensor wires. the ecu just goes off the voltage for WOT. you would need to install a switch yourself that simply gets triggered by the accelerator pedal. it isn't that hard once.

[Bitsushiti]

Ah no worries, thanks for confirming Hugh. I wasn't sure if it was going to be as simple as splicing a wire on the ecu harness.

Instead of setting up a switch for it, I reckon I'll just ground that wire instead and use the data out from the WB gauge to my PFC datalogit for checking peak AFRs.

Thanks again