This is how you adjust the throttle cable that goes to the tranny on a 22re, may be the same for 3.0

 

Hey Guys,
Still haven't figured this thing out. I tried a new ECM to no avail. The tranny in Overdrive off mode will downshift from O/D to third very sporadically like its not sure which gear it should be in. It will occasionally shift from 1st to 2nd with the shifter in L, but will only stay in 2nd very briefly and then shift back to 1st. In O/D off mode everything works fine when I shift manually, but still no 2nd gear. Could it be a speed sensor? I'm running out of ideas. I applied voltage and was able to hear the solenoids engaging in the tranny so I don't think its the solenoids, but I could be wrong there too. Any help is appreciated.

 

The cable only affects line pressure (How "hard" the shift feels). The actual decision to change geas is entirely electrically controlled. This is why the transmission will never change gears with the computer unplugged.

The ECT computer receives a speed signal from a speed sensor, and a TPS position from the engine's ECU, and determines what gear it should be in based on a table of values much like how the fuel system works.

If you're shifting strangely even with a new ECT computer, it's likely either a sensor or a bad wire. Have you tried reading the TRANSMISSION error codes as well? Many people know how to read the engine codes, but the trasmission ALSO has a test connector. and will flash codes though the O/D light.

Also, you can use a multimeter conencted to the transmission test conenctor to check the TPS output from the engine ECU to verify that the ECT computer is getting the proper signals.

 

I'm not able to try and read the Transmission codes because the O/D light doesn't have any bulbs in it and in middle of nowhere Idaho no part stores seem to have any. I unplugged the speed sensor to see if the transmission acted differently than when it is plugged in and there was no difference which makes me think it may be a bad ground or the speed sensor itself. Does anyone know where the speed sensor is grounded? The wiring diagram I have from the Haynes manual doesn't seem to match up with my 4 runner. Still have codes 42 and 51. I actually tried a new ECM not an ECT and saw no difference. Any more thoughts? I'm thinking speed sensor or something within the speed sensor circuit, or maybe a bad ECT.

 

The light on the od indicator should be the same as the ones on other switches in the cab. Check the rear window up switch. Just an idea to help you trouble shoot a little more.