95, Started surging up as high as 1400 at idle when warmed up. Had a 21 code. Helms says when you change the TPS you have to use a Tech 1 to teach the computer the new TPS settings. As I don't have a tech 1 how critical is this and is there any way around it

 

This is my 2 cents for now but will look in the book tonight. I thought the older TPS units had to be set up but not on the 94 and 95s. Are you sure yours is bad. You can measure the output wiper voltage which is 0 to 5 volts. Can do it with ignition on and engine not running, It should be a smooth transition while opening the throttle. I do have a Tech 1 and although pretty familiar with it I might not be a “super expert”. However I have not seen this function where you set up a TPS. It will measure the output voltage and percentage opened as I open the throttle of the TPS. It should correlate with manual testing.

There is a possibility I am not familiar with that set up because I don’t have that software. I do have engine, transmission and chassis software but have not come across that ability. I thought I once read where a set up was not required but I would not disagree with the FSM at this time. I definitely would ask around. If you disconnect the battery you will reset the PCM and ground zero learning process will start. I just don’t know if that would take care of the alignment if you do have to replace the TPS.

 

Jeff,
It is not necessary on a 95 to use a Tech1 tool. All you need is an ohm meter to either check a stock TPS and/or set an adjustable TPS. You can buy a plug in adapter to go inline at the TPS to help check this. Don't remember at the moment where I got mine.The engine will relearn the new setting as long as its within approx. tolerances of .54 volts +/ -about .08. I think any more or less than say about .45 to .65 volts will probably set a code. I use an adjustable one and have tried raising the voltage at closed throttle as high as possible to try and achieve 5 volts at wide open but could not go past about .67 before I got a code and engine was unable to learn the setting. Ended up running about .62 closed and 4.8 open. This merely advances the required voltage signal needed to the computer for WOT fuel/timing tables during part throttle acceleration.
Rick

 

I just happened to have my Tech 1 out so I looked at the TPS voltages. Closed throttle indicated 0.62 volts and open indicated 4.15 volts. Seems like in the past when I actually measured the WOT point with a voltmeter it read more. I will have to recheck that again.