One day you start up your vibe and are greeted with 3 lights on your dash.
1. Check engine.
2. VSC (Vehicle Stability Control)
3. Traction Control Off
Maybe your car seems to be running fine, maybe the warning lights don't even stay on for long, but you take it to your local parts store for a quick scan and pull up this code..
P0793
The details read "Intermediate Shaft Speed Sensor [A]"
If you have no other codes, then that is exactly what the problem is. It is a speed sensor on your transmission, nothing more, though there are misleading mechanics and forums out there that will try to scare you into replacing the PCM and all the wires because this is one job where the part is more expensive than the labor (which shouldn't be more than 30 dollars for this 15 minute job depending on where you live) and the replacement sensor costs right around 100 bucks.
If you're super tight on cash and haven't noticed any serious effects of this failing sensor yet, it shouldn't harm anything if you need to continue to drive your vehicle for a few days. However, keep in mind that without this sensor to guide it, your transmission may behave somewhat erratically, unsure of which gear it should be in at a given speed. This could mean refusing to shift beyond 3rd gear, stalling when the rpms drop due to a delayed downshift, or jumping to 4th on takeoff and leaving you near powerless in the middle of a busy intersection. Use your best judgement. For the record, I drove mine (2009 Vibe GT 2.4) with these quirks for 2 months before I actually fixed it thanks to first pursuing a lot of misinformation I got from the dealer and 2 separate transmission "specialists" in town... I don't recommend doing any of that.
If you decide to replace it yourself, like I eventually did.. note that the sensor to which this code refers is one of two accessible from above, slightly hidden under your air filter (take that off first and you're golden). If you don't want to lose an extra twenty minutes, replace the one on the left, near your transmission dipstick (like I DIDN'T at first). The other is awkwardly under the battery and shouldn't be as tempting anyway.
You may need to have the codes cleared once you've finished.
I hope this helps someone. Cheers!