2006 Jeep Commander acceleration problem

From the way my son describes the problem it sounds like a broken cable (but he says lifting up the accelerator it kind of starts to rev. Why can’t life be simple). I can fix it this weekend but I’ve seen references to both a cable for that car but also a throttle position sensor. My understanding is a car has one or the other so does anyone know which it is for the 2006 Jeep Commander? Or if it has both what does each do and which, given the symptoms, should I plan on replacing?

that vehicle has throttle-by-wire, there’s no cable. are there any warning lights on which look like these?

(as an aside, older cars with cable-actuated throttles still have throttle position sensors. in that case, all the sensor does is tell the PCM how much the throttle is opened. Modern cars with TBW incorporate the position sensor into the throttle actuator motor, and the PCM uses it as feedback to ensure the throttle is opened to the commanded position)

I got home and turned the Jeep (my son had it towed) on. Throttle worked fine. Don’t know what the problem was.

ooh, I missed the part about “starts to rev when lifting off the pedal.” maybe intermittent vacuum leak?

Car wouldn’t move today. The shifter seemed very stiff but it was 10[sup]O[/sup]F at the time. The dash shows it is shifting and it went into neutral fine. It just won’t go forward in drive or backwards in reverse. No the parking brake was not on.

Oh and apparently it did drive a few feet today. My son was driving and not me so I dont know the exact circumstances but he anaged to get it into the middle of the street before it failed.

Checked transmission. Very pink and if anything it is overfull.