I had a problem with my Q that would make it stall randomly on the road. More accurately, the RPMs would cut out, and even if I floored the pedal, it wouldn't rev past 2k rpm in 1st gear. The VDC and SLIP light would also come on, as would the "CHECK AT" light sometimes. I would have to turn the car off, wait 10-15 seconds, and turn it back on, and sometimes that would fix the problem. The computer threw codes p0225 and p0507 (If I remember correctly). After doing some research, it looked like the throttle body's throttle position sensor. They don't sell the sensor separately, so I had to get a whole new throttle body. Went ahead and ordered a new one from Rockauto for $140 (-40 for sending back the core). The dealership was selling the part for ~$700. Replacement pictures below.
That beautiful V8. Sorry if the picture is rotated wrong - imageshack was giving me grief.
The old throttle body is there, connected directly to the block. EDIT* Oops, that's actually the new one. I guess I don't have a picture of the old one in place like this.
Took off the intake and sensor. Make sure you're careful with the hose that goes off the intake. It looked delicate.
Decided it would be easiest if I just took the intake off to have some extra room to work. Next step is to remove the throttle body by taking out the four bolts on the corners
Off it goes! There's that middle piece in between the block and the throttle body that has some hoses connected to it. Not sure what it's for. There was some smoke coming out of the engine after I took the old TB off.
I actually messed up here by getting one of the wrong gaskets, so of the two there, I had to reuse one. It seemed fine, though. I cleaned it and the surfaces off and put it back in place. Someone please tell me if this is a mistake.
The new throttle body, bolted on.
Intake back on, sensor plugged in. Started the car, and all appears to be well! The sensor still has to be relearned, and that's $130 over here in NYC at the dealership. Going to get on top of that sometime this week as it's making the car act funny.
The old TB. Notice that residue...
Close up.
Overall pretty easy fix. Never thought I'd be doing work like this on my own!
