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Discussion Starter · #1 ·
Hello fellas,

I've got a 89 Cressida with a weird problem.

I'll try to explain this the quickest and easiest way I can.

Say I am going 40mph, and want to pass a car. Normally, you'd press the gas down how ever far you want, and the transmission would go down a few gears or less.

My car just won't do it. If I press the gas pedal to the floor, it does not downshift.

If I press the O/D button, the transmission quickly goes down one gear, which is what I use to pass people or get on the highway.

The engine itself is running perfectly with no major issues.

What should I look into doing? Any troubleshooting procedures I can look at?

Thank you so much in advance, I hope to resolve this issue.
 

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Cressida nut
91 Pickup (Hilux)2wd
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4,586 Posts
either it's a TCM/ECM (same computer in these cars) or TPS issue. I'll PM you a link (can't publicly post TSRM info due to copyright)
 

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Discussion Starter · #3 ·
either it's a TCM/ECM (same computer in these cars) or TPS issue. I'll PM you a link (can't publicly post TSRM info due to copyright)

my money is on the TPS. I have had a lot of trouble with it. I will buy a new one soon, and install. (using TSRM)

I will update when that time comes.
 

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Discussion Starter · #4 ·
my money is on the TPS. I have had a lot of trouble with it. I will buy a new one soon, and install. (using TSRM)

I will update when that time comes.
Alright, so I have a question here...

You don't need to remove the throttle body to properly get the TPS aligned with the inner pegs correct?

For some farking reason, I can't seem to get the metal pegs into the appropriate slots on the TPS.

It seems no matter what I do, they do not line up. It is just pushing the throttle plate open and not moving the actual sensor.

I'm kicking myself in the a** because I should have never removed the TPS when cleaning the throttle body. Too careful i guess.

Let me know what you think,

Thank you in advance,
-DJmart
 

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Cressida nut
91 Pickup (Hilux)2wd
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4,586 Posts
you might be trying to put the metal tabs on the wrong side of the TPS tabs. they should go on the flat side, not the notched side. either that or your TPS is sticky and you need a new one. it is possible to disassemble it to clean it but that won't guarantee it's still OK electrically plus you have to break the tabs that hold the back cover on to get it off.
 

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Discussion Starter · #6 · (Edited)
you might be trying to put the metal tabs on the wrong side of the TPS tabs. they should go on the flat side, not the notched side. either that or your TPS is sticky and you need a new one. it is possible to disassemble it to clean it but that won't guarantee it's still OK electrically plus you have to break the tabs that hold the back cover on to get it off.
I do believe that the tps is in wrong. It seems to me that the throttle plate shouldn't open up when pressing the connector side down. (ccw

It isn't stuck and it does work, as the motors rpm changes when playing with the sensor off of the throttle body.

Any further instructions or pictures that would Aid in installing the sensor? Mad I ever took it off.
 

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Cressida nut
91 Pickup (Hilux)2wd
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I do believe that the tps is in wrong. It seems to me that the throttle plate shouldn't open up when pressing the connector side down. (ccw)
it does actually. looking at the throttle body from the rear of the car, the shaft rotates clockwise, which means the right side (toward the connector) will rotate down. I don't think any bolt-on toyota TPSs spin the other way (7m, 1j, 2j, 22r all go the same way). it also has a stop, if it didn't turn the right way, either the tangs would engage it and the whole thing wouldn't move (or would break the tangs off) or it wouldn't engage the tangs and would stall out when you touched the gas.
 

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Discussion Starter · #8 ·
it does actually. looking at the throttle body from the rear of the car, the shaft rotates clockwise, which means the right side (toward the connector) will rotate down. I don't think any bolt-on toyota TPSs spin the other way (7m, 1j, 2j, 22r all go the same way). it also has a stop, if it didn't turn the right way, either the tangs would engage it and the whole thing wouldn't move (or would break the tangs off) or it wouldn't engage the tangs and would stall out when you touched the gas.
I finally got it!

I did have the TPS in wrong, it was not on the flat side on the inside.

It really helped to have the throttle body off of the car to get a better visual.

The transmission is shifting as it should now.

All I need to do is tweak it to spec and I will be all set!

Thank you everyone for your input!
 

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Cressida nut
91 Pickup (Hilux)2wd
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4,586 Posts
In case you don't find one of my other how-to-install-TPS posts, just use a multimeter on the lower 2 pins (they're for the idle switch) and adjust the TPS so it has continuity when the throttle is closed, but is open as soon as you open the throttle. if the circuit stays closed a hair too long it's better than never closing (ECU will never think the cars at idle)
 
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