1997 Subaru Legacy wagon 2.2 I got a code PO122 Thorttle Positioning Sensor low ciruit feed. I have a new one ordered. My old one has been adjusted many times over the years so I have no idea where the new ones needs to be set, does anyone know any thing about these? There is about 3/8 in. adjustment on them.

 

The one I need to remove has the screw that is on the top towards the windsheild, the bottom screw is all of the way in opposite direction, or another way to explain it is the elc. plug is pushed as high to the hood as it will go. Thanks for any help or suggestions.

Going by what the code states, 'Throttle/Pedal Position Sensor A Circuit Low Input' the trouble is most likely with a connection between the TPS and the ECU and not the sensor. If the wiper of the sensor is not making good contact inside the sensor and causing the error code then it will be good to replace the sensor. By checking the voltage of the wiper at various throttle positions you should be able to tell if the sensor is working like it should be.

TPS adustment:

 

This boils down to the "Idle Switch"

which is incorporated in the TPS housing.

 

This switch must be closed at idle and open

when the throttle is pressed.

 

To set the TPS ajustment.

1) remove the connector from the TPS

2) check between pins 1 and 2 for 0 ohms

showing the switch is closed.

Pins 1 and 2 are the two pins closest to the top of the TPS

[-] - #1

[-] - #2

[-] - #3

[-] - #4

as viewed from the front of the car.

 

3) Insert a 0.028" feeler gauge between the throttle and the

throttle stop, the switch should remain closed ( 0 ohms)

 

4) remove the 0.028" feeler gauge and insert a

0.035" feeler gauge

 

5) the measurement between pins 1 and 2 should now show

infinity - meaning the switch is open.

 

Adjust the TPS position so the above conditions are met.

 

Hope this helps.

Cougar, I hope it is the T.P.S. being I have already ordered it, maybe I should have asked first.

 

 

Skip, thanks, that looks like good information, I think I understand but I may have more questions when I start, so please check back if I repost.

TPS adustment:

 

This boils down to the "Idle Switch"

which is incorporated in the TPS housing.

 

This switch must be closed at idle and open

when the throttle is pressed.

 

To set the TPS ajustment.

1) remove the connector from the TPS

2) check between pins 1 and 2 for 0 ohms

showing the switch is closed.

Pins 1 and 2 are the two pins closest to the top of the TPS

[-] - #1

[-] - #2

[-] - #3

[-] - #4

as viewed from the front of the car.

 

3) Insert a 0.028" feeler gauge between the throttle and the

throttle stop, the switch should remain closed ( 0 ohms)

 

4) remove the 0.028" feeler gauge and insert a

0.035" feeler gauge

 

5) the measurement between pins 1 and 2 should now show

infinity - meaning the switch is open.

 

Adjust the TPS position so the above conditions are met.

 

Hope this helps.

Skip, mine only has three pins, do I do it the same as if it had four?

I believe so

two will be for the idle switch

 

the third for the potentiometer wiper arm,

 

One of the first two will be a "common" bewteen the two

devices.

 

Using your multimeter set on ohms

you should be able to identify the two for the

idle switch.

 

The reading will go from 0 to infinity when the switch is turned.

 

The other will progressively change resistance.

Thanks for the help, I got it running right.

Edited January 17, 200917 yr by tcspeer