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Well i just checked my TPS voltage to try and sort out an idling issue

I've read that it should be around 0.4v closed and 4v fully open

I stabbed the 2 wire plug that comes off the tps with a multimeter and it's reading 10.6v closed, while the car is running:blink:

With the car off it was 9.5v closed and 12.5v open

Am i taking the reading from the wrong place?

Anyone know why it's so high?

On an RB20 by the way

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It misses at idle and fluctuates from 700-900rpm

It misses and jerks a bit when shifting quickly on boost too

edit: There were 2 plugs coming off the sensor, one with 2 wires on the side of it and another one with 3 wires coming out from the bottom of it

I only tested the one with 2 wires, im assuming its the right one because the voltage did change when i opened the throttle

Edited by r32woohoo

iv managed to adjust my tps so it was ideling at a nice level but it still peaks at around 1100-1200 sometimes and other times when i start the car after driving it wont idle properly and will cut out/stall straight away. alot of the time it will fluctuate between 600-900 and cause jerking around 3000 rpm.

im thinking of getting a new tps so i can eliminate a faulty tps and also maybe clean my throttle body too, as i have already cleaned my aac.

other suggestions on the forum is the cold start.

Im guessing, but i think the 2 wire plug is for auto trans. The three wire plug is for the ecu. The only way that it can be above 5v is if there is a wiring problem, or the voltage reg in the ecu has short circuted, which is very unlikely. Unplug the tps, and check the supply voltage, should be 5v

iv managed to adjust my tps so it was ideling at a nice level but it still peaks at around 1100-1200 sometimes and other times when i start the car after driving it wont idle properly and will cut out/stall straight away. alot of the time it will fluctuate between 600-900 and cause jerking around 3000 rpm.

im thinking of getting a new tps so i can eliminate a faulty tps and also maybe clean my throttle body too, as i have already cleaned my aac.

other suggestions on the forum is the cold start.

i got some throttle body cleaner and gave it a good clean. started my car and it idled at 1100 and within about 10 sec it bounced to 1500!. i then adjusted my tps so it droped to 1100. took it for a quick drive, to see how it goes with a clean throttle body, and wouldnt idle lower than 2500rpm! after i got going.

mind you it wasnt fluctuating when idleing, probably cause it was idling to high

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