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vl link tps question

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Hi guys, I just have a question about my tps on my rb30 vl turbo using a xf tb with factory vl tps. I do tps calibration no worries, follow on the screen instructions. I get 0% throttle at rest and 100% at full throttle with 4.86v on the gauge in the link software at rest. But here's my issue. I'm not getting any in between reading only 0% at rest and 100% fully open. I'm not getting 25% or anything while at idle if i raise the idle to 2500rpm is this normal or do i have a faulty sensor? I thought when you raise the idle the tp % should change so the ecu knows how much of a enrichment the engine needs. My analog sensor (automatic vehicle sensor) is wired up to the factory throttle switch plug wiring. The power signal, a 5v and a chassis ground.

I'm not sure I understand completely? Are you saying that you only register 0% or 100%? In this case it sounds like you've wired to the throttle closed switch which was common in quite a lot of older throttle bodies. These sort of TPS usually have 4 wires. It's easy to test by watching the analogue voltage input and seeing if it moves smoothly or just switches.

The idle speed is controlled by a separate idle air control valve and this is not related to the throttle position (like it would be with a dbw throttle body). This means that you shouldn't expect the throttle position to change if you raise the idle speed using the IAC valve. If on the other hand you're cracking the throttle stop to adjust the idle speed then this would bring me back to the first point above.

Yes, i'm only getting 0% or 100% I wired up a auto tps (used the white plug in picture) which was recommended in the link booklet. I wired up the sensor to the factory throttle switch wiring which is a signal power and a 5v. I grounded the sensor on the chassis of the car. I'll check and test the wiring again. Thanks for clearing that up, I am cracking the throttle stop to adjust idle speed.

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I do get 97%, 98% just before wot but nothing before that, I see the voltage in the link software change down to 0.05v at wot.

That white plug should be the correct place to wire to. I'd suggest using a multi meter and confirming there is a variable resistance between the signal terminal and either the 5V or 0V terminals as you move the throttle.

Just checked the signal wire, i'm getting around 4.32v value on the multi meter. The value moves around a lot at rest. As I increase the throttle opening the value increased by about .4v to .7 v increments as the throttle is opening. The signal wire value at 100% throttle is 0.05v to 0.00v. The 5v wire stays at 5.00v, there is no change in value.

Also set the multi meter to ohms for resistance, I can only get a reading from the throttle switch on the tb, not from the wiring to the white plug? or if i plug the probes from the multi meter into the back of the connector.

Turned out to be a faulty tps sensor.

Glad you got it sorted!