Resistance is futile, voltage is a much better indicator of what is happening.

The TPS has a sensor circuit and a switch inside. There are four wires: E2 - ground; IDL - idle circuit (on or off); VTA - variable voltage signal (varies with throttle position); VCC - 5 volt reference signal. If the idle switch in the TPS is closed (E2 and IDL connected), the computer will disregard the variable throttle signal. If the IDL wire between the TPS and computer is shorted to ground anywhere, the computer sees this as the switch being closed and implements its idle speed limiting strategy. I would check for ground at pin 6 (or maybe it is 8 - whichever has the black/white wire) at the 18 pin connector (the middle one) of the computer with the throttle open. You should be able to see the signal change as the throttle is opened and closed. If this circuit is always grounded, then you have narrowed down your problem. I hope this makes some sense and I haven't just made things more confusing. I'll try to check back later and see how you are doing.

DOH! On my 4Runner, the IDL circuit wire at the computer is only black and it is in the #6 pin position. With the key on, simply backprobe the wire with the ground lead of your meter at the connector and put the positive lead at a 12 volt source. You should read battery voltage until you press down on the gas pedal, then there should be 0 volts.

The FSM shows them all, cab is behind the driver's side kick panel, and probably one over by the ECU in the passenger side kick panel area. Engine is back of head, and around the intake, battery, fender and frame.

Ran perfect yesterday, runs fine today.
Hopefully it stays like this untill the weekend. If you've read any of the other threads, It only does it once a week and usually in the most unwated times, like on the way to a big catering gig. Never when just shopping or casually driving.
Tomorrow I'll pull the ecu and do a volt check, then keep it out for when it decides to cut out on me. Had it sitting on the passenger floor for a week last time I did tests.

I hate on again off again problems. REALLY hard to diagnose.
I'll check in after the tests <img src="/forums/images/graemlins/kewl.gif" alt="" /> <img src="/forums/images/graemlins/cheers.gif" alt="" />

It started again, then stopped, so I'm going to hook the voltmeter to the ECU and leave it there so I can do a real time diagnostic.

Hey, I have three meters,
any other places that may be helpful for me to leave hooked while operating under normal conditions? <img src="/forums/images/graemlins/confused.gif" alt="" />

<img src="/forums/images/graemlins/scared.gif" alt="" /> Get the truck running and shake the injector wiring harness that runs below and thru the intake plennum.There's a crimp connector in this harness that can come apart and cause intermittent problems.Hope this helps. <img src="/forums/images/graemlins/cheers.gif" alt="" />

Tried shaking the wires with no reaction.

Pulled the whole harness last summer, stripped the casing, soldered those pesky crimps even though they were tightly intact, and soldered them properly, clean tight solders too

(anyone remember the sevice guy who posted on the miltary soldering guide via a Navy(?) solderer last August or so?)

I've done alot of harness shifting trying to eliminate or reproduce this problem.

Maybe I'll pull that whole harness again just for kicks n giggles cuz I'm gona go crazy <img src="/forums/images/graemlins/drunk.gif" alt="" />

I had the same intermittant shut down/stumbling along with no error codes as you described. New (used) fuel pump in the tank did the trick. Always seemed to run fine while just cruising, but once I let off the gas while slowing down, that's when mine would slow down until it died. Pumping the throttle while this was going on had no response what-so-ever.

>>>*Sounds like an old Dodge I had once. I chased electrical and fuel filters, etc, not really that tough on those old rigs.

Finally it hit me that it was just uphill under load or at higher speeds.

As speed picks up, volume of fuel moved picks up. Turned out to be some water in the tank, the pump would move the fuel at slower speeds and begin to pick up water at higher speeds.

*Just a thought....*EB

I had a 1977 Celica, 22R that when driving steady, ran fine. If I tried anything else, higher rpm, any slight incline, it cut out. I diagnosed everything under the sun <img src="/forums/images/graemlins/confused.gif" alt="" />
and finally changed the fuel filter. That thing had so much sand in it!
Drove me crazy, that car <img src="/forums/images/graemlins/baby.gif" alt="" />
Ran like new after the filter change.
Just a thought.
Danny