Just purchased a used Volvo S60 from 2002 with a modest 140k miles and leather seats, a welcome replacement for my problematic '01 base Cavalier. Unfortunately, it appears my throttle position sensor is going out. Take a look at my symptoms and see what you can figure out:
1. Extremely rough idling - Lurches while sitting in drive, shakes while in neutral or park
2. Pedal position - Can only be pressed slightly with minimal acceleration to boot. Pushing down harder warrants either constant speed or deceleration due to the changing of gears despite no increase in speed.
3. ENGINE SYSTEM SERVICE REQUIRED message appears after the engine starts idling rough.

The engine sounds great while I'm moving and the transmission shifts as smooth as butter, but I'm keeping it parked until I fix the issue due to the imminent wearing out of the motor and transmission mounts.
My questions are: Do these issues sound like a faulty TPS? and Where can I get a good used one for cheap? I would try a junkyard since I'll be doing mostly low-mileage commuting but it seems like these sensors go out a lot.

Any help would be appreciated!
- Luke

 

You need to first verify that it is the throttle body. For a 2002 model, they are relatively inexpensive and do not need programmed like the 99-01 models did. Before doing anything, I would remove the throttle body, clean it on both sides of the butterfly, then read the codes in the car.

In any event, you can find them new all over as the basic design is shared by other manufacturers and I believe that the unit was originally built by Bosch.

 

I haven't had this happen on a Volvo, but I have on my Dodge truck. The circuit is triple redundant, so the second one system doesn't match the rest, you get the check engine light. The car gets confused and starts shifting gears when you barely touch the pedal, but typically the idle circuit is NOT effected.

I'm not really understanding your symptom list.

1. the car idles bad. I get that.
2. Explain the part about the pedal position. You say the car runs great when moving, but you have minimal acceleration. Are you saying you barely touch the pedal and the car downshifts? Is it not accelerating at all ever?

Also, don't buy electronics from junkyards. They probably have the same problem yours has.