That's what i plan to do next, and see how that goes.
I think more than anything it was because i had purchased a duralast TPS sensor from Autozone, the day after i had the code. When i had replaced the throttle body, it had come with an original TPS. So being old (from the junkyard) it could have already been on the last leg. Thenwhen that failed and then got a non start from the TPS sensor i bought from autozone, it sounds like my luck. After looking at the forums more, i noticed that the Jeeps do not like the aftermarket sensors. So going to order a new one and see if that does the trick.
Some do, some don't. My 93 has zero mopar sensors. The IAC, IAT, TPS, MAP, coolant sensor, cam sensor, and crank sensor are all Autozone or RockAuto and it runs fine. No stalls, bucking, surging, roughness, or weird shifting and it passes emissions fine every year. I've also had Bosch, Denso, and NTK (current) O2 sensors in it with no noticeable difference.
Not saying that people haven't fixed their ZJs by buying OEM sensors it just seems to vary from Jeep to Jeep. There's an element of confirmation bias here I think.
Its simple to test you TPS. Backprobe from center pin with positive and put neg to ground. Turn ignition to run (dont start). Voltage at idle position must read greater than 300mv and gradually increase to around 3.8 - 4.8 at WOT. If the voltage is inconsistent anytime during the test, your TPS is bad. It must start above 300mv and gradually go to 3.8 -4.8 when you move the throttle by hand. Your going to spend a fortune if you keep troubleshooting by replacing sensors. Your multimeter is your friend...
I tested my last TPS, and at full throttle i was only getting 3.1V, and that was a dealer one. So i am going to exchange that one. I am getting 5V off the connecter. I must be the unluckiest guy in the world with TPS sensors lol. Hopefully my replacement one will be here tomorrow or Wednesday.
I don't think 3.1 volts at wot is going to hurt anything. The main thing to look for during the test is a sudden spike (hi or low) in voltage. Mine is original from 93 and it hits about 3.3 at wot. Did you ever find out how much voltage the alternator is putting out?
I did, i dont remember what it read it. Ill have to recheck again when i get home, but i believe it registered normal (so many readings over the weekend lol). With that 3.1 V with the new TPS it still popped codes with the rough idle/surging etc. 22, 23, 24 (along with 12 for battery disconected and 46 battery voltage to high or low). The first 2 codes (22,23) just now popped up after installing this new TPS. Before it was only the TPS sensor code popping up.
When you "told the PCM where full throttle is" ... why did you step on the gas twice?
So, the process is.. Unhook and rehook the TPS. Then turn the key to ON. Then push the gas peddle full and release... TWICE. ?
Then start the Jeep.
And you burned through another TPS? What happened? I mean I am having basically the same problems you are.
Well that is what worked for me, reading off another forum. However, now i am thinking that was a result based analysis, and not the actual problem (or fix). As it died again about 10 miles later. Unfortunately, i have not had time to work on the jeep, and when i have, its been raining (its outside in the driveway, on a 45 degree incline. Yay!).
While its still throwing a TPS fault code, I'm thinking that is not the actual problem (think my TPS sensor are ok), but the voltage being supplied to it is low (causing the code). Rich has suggested i test the alternator, and that is the plan tonight after work (weather permitting, damn you Washington state!). I will bring my laptop out there, and update as i go through things. I'll start with the alternator, then check for bad grounds and wiring, and im going to do some vacuum leak tests.
There is a slight whistle coming from the upper part of the intake somewhere. I noticed it when i replaced the TPS sensor the second time (the one that worked), and then it stopped about 1 minute after startup, when the idle stabalized. After replacing that TPS, that whistle returned during the poor idle.
Some other things to add, when the car is started and idling (roughly) my volt meter reads about 9v, and then would immediately jump to the regular reading of 14v when it recognized the TPS (or the vac leak closed up on its own, or whatever the issue was corrected itself for a short period). With the current TPS sensor, that volt gauge in the dash is just sitting at 9v and only goes up slightly as the erratic idle goes on its upswing.
Oh, and to actually answer your question, the reason they gave for this process,
install TPS, reconnect the sensor, reconnect battery. Put key in ignition and turn to on (not starting the car), wait for 30 seconds, then depress the gas pedal and hold for 6 seconds (make sure no floor mats are blocking the gas pedal from fully reaching the floor), release gas pedal for 6 seconds. Reapply pressure on the gas pedal for 6 more seconds and then start the car (without aide of the gas pedal).
By doing that it is telling the PCM where full throttle is on the TPS and calibrating itself from there.
******Disclaimer******** This worked for me on that 1 sensor (lasting about 10 miles), I believed at the time, that that is what fixed my problem. It has not worked since then for me. It was taken from a different car forum, and i thought i would give it a try on mine. Everything i have read about the Jeep TPS sensors is its a plug and play, with no ability to modify or "set" them.
Starting at step 1, and going all the way through. I'm not sure if you have seen that thread or not Tully, but there is some tremendous information in there. Once i figure out exactly what it was, ill make sure to repost here.
Flash....Can you give us a current status on what your Jeep is doing at the moment. I.E, It will start and run with poor idle, Still trowing a code for TPS, Alt voltage is ????? when checked with a multimeter. ECT.
Currently it starts, idle rough (sometimes dies), idle surges. Still throws a code for the TPS, will sometimes throw a code for the 02 sensor (21).
22 Engine coolant temperature sensor above or below acceptable voltage.
23 Intake air temperature sensor input above or below acceptable voltage..
24 Throttle position sensor input above or below acceptable voltage. TPS signal does not correlate to MAP sensor.
46 Battery voltage too high during charging or charging system voltage too low
Of course i will get the code 12 for battery disconnected.
The only static code though is the 24 and 46
Looks like i might be able to get a reading on the alternator tonight (weather permitting)