ok so i have a friend took her car to the dealer cuz check engine light came on. they dio tested it and said it needed a new thermostat and sensor, didnt say what sensor though. told her the bill would be 380 range to fix it. i looked up thermostat and took car to advance auto and they ran there machine and said it was the throttle postion sensor. will the car still start and drive fine if that sensor is bad? or what will happen if the sensor goes completely? any help, ideas ect would be greatly appreciated. thanks.
Chad

What specific fault code number did they get ? Even though you may have several codes, sometimes they can both be fixed by changing one item.
I recently had a EVAP system and knock sensor code on my 98 Altima.
Someone on these boards advised me to change the EVAP perge valve first.
After I changed it that code went away immediately. After driving about 30+ miles the check engine light went out on its own and I never changed the knock sensor.

Typically the biggest problem that occurs when a t.p.s. goes south is harsh shifting or erratic shift quality. Yes sometimes they can run alright and seem to have almost nothing wrong with them, but they can also cause a vehicle to run rough and die as well. If the dealer failed to name the related sensor for the repair, I beleive you have the answer to whether or not to ever return to them again. Just a little side note to mrbizness1, the knock sensor does store a code however will not turn a light on. Trust me, you still have a code stored in memory for knock sensor.

Just a little side note to mrbizness1, the knock sensor does store a code however will not turn a light on. Trust me, you still have a code stored in memory for knock sensor.

Interesting, I will have to check this out.