TPS Adjustment - My Findings

[Stu]

Thanks, so it's the starting point you adjust, so it can have an effect throughout the rev range.

Originally Posted by Stu

Thanks, so it's the starting point you adjust, so it can have an effect throughout the rev range.

Can and will. However, I reckon (having done the TPS adjustment) that this is a very small difference.

Once you make the modification, the throttle moves less to increase (I'm assuming it's an increase, I haven't tested) the resistance given, which drops the current flowing to the ECU.

Obviously if you change how soon this resistance (by removing the null area of throttle play - as far as the FI is concerned), there will be a greater resistance at any given throttle position after the adjustment is made, when comapred to before the adjustment is made.

However, due to the nature of the device used as a TPS (yo-yo resistor), this is likely to be very small.

So yea, an "improvement" at all revs, but the higher the revs go, the less difference is noticed. Or at least, that's my findings.

[Sid Squid]

Originally Posted by Stu

Very now.
The TPS adjustment is adjusting when the line moves from the middle of the screen to the top. Which to me sounds like an on off switch.
What Baph says makes sense, but does not equate to the sensor having 2 positions IMO. Who is right?

Wrong. The TPS is a potentiometer, the display is a voltmeter, the throttle position is indexed as a voltage by the FI/ignition system electronics, the system doesn't 'add more fuel' when the display changes, the throttle position is one of a number of variables the system uses to set injector duration and ignition timing, I suspect the TPS's most noticable effect is ignition, I imagine the timing is set for idle stabilisation.

Originally Posted by Sid Squid

Wrong. The TPS is a potentiometer, the display is a voltmeter, the throttle position is indexed as a voltage by the FI/ignition system electronics, the system doesn't 'add more fuel' when the display changes, the throttle position is one of a number of variables the system uses to set injector duration and ignition timing, I suspect the TPS's most noticable effect is ignition, I imagine the timing is set for idle stabilisation.

Potentiometer - technical term for a yo-yo resistor

If it measures current or voltage, it achieves the same purpose.

Whether is increases the fuel squirted by the injectors or not, well, that's internal combustion, not my game. Surely it's a variable in the amount of fuel used though.