I have an '04 CLK55 where I've had the car go into limp mode after trying to kickdown when merging onto the freeway. The 2nd time it happened I pulled the codes and got P0123. This seems to indicate the TPS/Pedal Position Sensor. From googling around it also looks like that a faulty sensor would also explain my sometimes touchy/erratic throttle.

It looks like the W209s do not have a TPS sensor like the W208s and therefore you must replaced the accelerator assembly.

I couldn't find the exact part on any of the parts catalogs when trying to browse by diagram. I have two part numbers I've found, but not sure which (if either) is correct. Can someone confirm the correct part number? I've seen:
2033000604 and 2033000904.

When I punch these into the parts catalog at the local dealer's website (Smythe in San Jose) it says it can't confirm these are the correct parts.

Thanks in advance.

In case anyone else has this question. I Ended up calling up a dealer and gave them my VIN. They quoted me the part number 2033000904. Looks like this part supercedes the 2033000604 part number. The old accelerator had the 0604 part number.

Replacing it was a snap...took all of about 15 minutes.

0604 on top, 0904 on the bottom.

Meh, double post.