MB

WOT is Wide Open Throttle, ie when your foot is flat to the floor. At this point the ECU goes into open loop fuelling control - ie a preset fuel map. Im used to a voltage of 0.85 on WOT....

MB

Paper Lawyer

That's because you're a hard man Mark




(and I was simply looking for a high voltage image using Google )

MB

Er, thats fairly disturbing

(Think its beacuse turbo's run with a higher safely margin, therefore more Rich)

MB

Paper Lawyer

Surely the WOT voltage is entirely dependent upon the particular sensor set up, rather than whether its an NA or FI engine? I can't imagine there is a particular rule to this, perhaps you can could have a voltage measurement between 11 and 12 volts, if you wanted to? (although I'm sure there's a reason why the voltages are kept low).

MB

Sorry, hadn't realised you replied!

The sensor is reading the residual oxygen left after combustion and all the Bosch / NTK sensors are 0-1 volt on the same calibration AFAIK.

So 0.6 is the same car to car. What is governing the fuelling is the MAP and the fuel maps in the ECU. It maybe that these cars run that bit leaner compared to an impreza. They are know to run rich to keep cooler combustion.

You could have the volts between 11 and 12 as long as that 1v between is the same scale. Not sure why you would want to, and im sure there would be issues doing this.

Im going wideband though so not too fussed!

MB

Paper Lawyer

I see! I'd have assumed that a Scooby would run a similar A/F as the FI S2000s - perhaps 12:1 (or maybe as low as 11:1) rather than 14:1 ?

MB

FI it would, but not N/A

12:1 I would be content with.

MB

GSi

Not that I have much idea what you're on about but that final diagram states 4.8V at WOT on the TPS. Where are you measuring the voltage?

Paper Lawyer

We are (or at least I am ) looking at the o2 sensors - terminals 15 and 16.

MB

MAP is calcing air flow, we're talking about lambda (fuelling)

MB