This is the Bad A* sensor. It has to work well to avoid problems from idle to the midrange. It has less effect the further the throttle blades are opened, so not so much a problem for wot. The reason it is so important is that the MachZ calibration is Alpha-N.
Everything you ever wanted to know about the TPS can be found with the following Google searches. So I won't cover all the details, just a couple things that don't get much attention. BlueMax TPS site:DooTalk.comThumbdoctor TPS site:DooTalk.com
With the CanDoo I get to perform the TPS reset myself and see if there is any truth to what I read, and there is. Below are some interesting instructions from BlueMax that I got to try for myself and found the reason why with a 600 SDI that was running lean and kept backfiring. As I was backing-out the idle screw the TPS value showing on the CanDoo reached zero and it still had over a turn to reach the zero stop! Not good. It could also have meant the sensor itself was bad or worn out.
The techs at CanDoo found that dirt/dust particles could accumulate on on the carbon trace between the zero stop position and idle where the wiper never reaches other than a TPS reset. This could mess with TPS reset and through-off the Throttle Position a few degrees. I think this was a problem more prevalent with older TPS, but if everything has been done to solve a Lean Midrange to no avail, this sensor may need to be replaced. The reset takes 15 min and the results show-up immediately on the Air/Fuel Gauge. BlueMax Posted 20 February 2008 - 11:54 PM"If the dealer did not make sure the throttle blades were against the throttle body zero stops, it may have been set incorrectly. Sometimes there is dirt in the throttle bodies that prevent throttle blades from getting to zero stop. Also they may have forgot to make sure there was slack in the throttle cable or may have even forgot to back off idle screw completely. A good tech will always look at throttle blade position when first hooking up BUDS system. Then he should back off the idle adjustment screw to see if the blades reach zero degrees. If this does not happen, it is time to take a much closer look at all components before doing a Closed Throttle Reset procedure." http://www.dootalk.c...t/#entry1673614