TPS questions

hey everyone,

I recently replaced my Throttle position sensor and at first glance all was well, but the car started doing some weird things especially when driving for longer periods of time. I believe it is misfiring? sort of a lack of power when accelerating.
I’ve been tinkering w the TPS position today, using a live data scan tool, and my issue is at the maximum counter clockwise postion the scan tool still shows it at 3.1% when the throttle is completely closed ( wont adjust to 0%, as ive readit should be). I made that adjustment and drove around the block and is say I got worse.
Any insight on this? I’m having trouble finding info on this specific issue. figuring I might need to locate a voltage meter and try to go that route, or is there something I’m missing using the code scanner?

Thanks.

What model,year,milage on your Subaru?

'04 forester almost 180k. I just needed something and it was cheap. it wasn’t having these issues before replacing the sensor.

What was the reason for replacing the sensor in the first place?

Where did you get the new sensor?
Aftermarket parts can be a roll of the dice.

AT oil light was on, car wouldn’t start, and the codes pointed to a bad TPS. the idle air control went at the same time which seems fishy to me.