As an experiment today, I pulled all three connectors off the throttle body. IIRC, APPS is on the PS, TPS on the DS, plus power for throttle servo (I may have the acronyms backwards, if so please forgive and correct for clarity). The result: truck is completely drivable with good power. For the 2000 LC, a TBW failure will not leave you stranded.
This was discussed briefly in another post, but at that time I had not verified the results. How it works: in the 2000, the APPS is at the throttle body. There is still a mechanical cable connecting the pedal to the APPS. For the first 75% of travel, the cable pulls a cam which controls the position sensor, giving signal to the ECU to control the servo motor. At WOT (from the perspective of the sensor) the cam hits a stop that allows it to mechanically open the butterfly. The pedal becomes very sensitive as only 25% of throw yields large changes in throttle position, but it works. Plus the spring force is 2x so it's pretty touchy. But power is good. When you step all the way down, it scoots (as much as an LC can scoot anyway). From what I remember when last cleaning the throttle body it really only opens about 2/3 of the way but with a butterfly valve this is effectively full throttle at low RPM's.
Two items to note before you try: 1) I had previously adjusted out the slack in the throttle cable. If there is slack you will get less mechanical action and therefore less power. On mine, there was enough slack from 10 years of use that I doubt there would have been much (if any) mechanical action. 2) this will throw two codes (0120 and 1120) so if you try you'll want to have a code reader handy or you'll be looking at a check engine light for a while.
IIRC, on later years Toyota relo'd the APPS to the pedal and did away with the cable altogether. So I don't know what year range this applies to. But it makes me feel good to know that it isn't a single point of failure through the 2000 MY.
If you do adjust your throttle cable take care that you don't make it tight. It needs to have a little slack to allow for normal thermal expansion/contraction to not accelerate the engine. On mine, I left it so that finger pressure could easily create a little belly in the cable.
This was discussed briefly in another post, but at that time I had not verified the results. How it works: in the 2000, the APPS is at the throttle body. There is still a mechanical cable connecting the pedal to the APPS. For the first 75% of travel, the cable pulls a cam which controls the position sensor, giving signal to the ECU to control the servo motor. At WOT (from the perspective of the sensor) the cam hits a stop that allows it to mechanically open the butterfly. The pedal becomes very sensitive as only 25% of throw yields large changes in throttle position, but it works. Plus the spring force is 2x so it's pretty touchy. But power is good. When you step all the way down, it scoots (as much as an LC can scoot anyway). From what I remember when last cleaning the throttle body it really only opens about 2/3 of the way but with a butterfly valve this is effectively full throttle at low RPM's.
Two items to note before you try: 1) I had previously adjusted out the slack in the throttle cable. If there is slack you will get less mechanical action and therefore less power. On mine, there was enough slack from 10 years of use that I doubt there would have been much (if any) mechanical action. 2) this will throw two codes (0120 and 1120) so if you try you'll want to have a code reader handy or you'll be looking at a check engine light for a while.
IIRC, on later years Toyota relo'd the APPS to the pedal and did away with the cable altogether. So I don't know what year range this applies to. But it makes me feel good to know that it isn't a single point of failure through the 2000 MY.
If you do adjust your throttle cable take care that you don't make it tight. It needs to have a little slack to allow for normal thermal expansion/contraction to not accelerate the engine. On mine, I left it so that finger pressure could easily create a little belly in the cable.
