Hi Everyone,

I recently owned a Toyota Corolla 2008 1ZZ 1800 A/T 1800cc, but I've noticed a delay when I press the gas pedal. The delay is to be related to the position of the pedal rather than a time delay. When I press the pedal lightly, there's no response in the engine RPM. It's only when I press the pedal further or deeper that the engine starts to rev up. This delay is making driving less responsive and precise, especially in areas with high traffic jams and frequent intersections where I need to switch between the gas and brake pedals frequently.

I disassembled the pedal sensor but there was no way to adjust the angle. Has anyone else experienced this, and if so, what was the solution? Should I insert a wedge (1 to 2 mm) in the gap as a corrective solution?

I just contacted the official Toyota dealer/service about the Accelerator Pedal Position Sensor (APPS), and they informed me that the part has been discontinued and is no longer being produced. Do we have any alternative/substitution for this part?

Here is the link to the part: https://partsouq.com/en/catalog/genuine/unit?c=TOYOTA00&ssd=%24*KwG_i5qg_9bF7uPT8r2li-fz09TKu7S5uKqFtv74y8XIwfXWpKmwzb25ub25u83l6fbz4svxr_ips_aA5KGu6Ki3v_b3obOizfep6eToqbPn9uTr5e-ot668seTr5KGu4uSvtqm-7Ov0vbnJqPDy_eCwmr2v5f-ot67byIabi6-gqenurrGr5e_wvrq7qKGu5ur24OTX1s67ub3ZpJOfi8nH36ihru3gsPj8u6Cp_O6usavn4v7arvYAAAAAzgw4Yw%3D%3D%24&vid=&cid=1&uid=74713&q=

Many thanks in advance.

Cheers,

I pulled a TPS apart a few months back, it basically does the same job as your APPS except it sits on the throttle body.  Inside were fine bent metal arms rubbing on a set of carbon tracks that curved around a plastic disc. Obviously the first few mm get rubbed a lot, while the full throttle end of the tracks never gets touched. I expect you've rubbed the first mm or two away over the years, so on  a stock computer it is a throwaway, or at least a custom throttle stop job.

You could-

-Stop the throttle going all the way back to zero, although I expect there is an idle switch in there to tell the ECU to idle, and if you stop the pedal in front of that short contact the ECU will not know it is at idle. You might steal 2 or 3mm of pedal and still get idle. You would need a bolt on the floor to stop it returning all the way, something you could adjust.

-Study yours with a multi-meter and see exactly when it makes a circuit. Then head for a wrecker and search for one that switches on earlier. I expect most old Corollas suffer the same problem.

The Haltech ECU I fitted recently asks you to click on a computer when you have zero throttle, and again when you are holding full throttle, so Haltech don't worry about where the pedal is in reality, they set the ECU up according to where you want idle. Sadly I doubt a Toyota ECU can do that.

 

On 10/23/2024 at 10:09 AM, altezzaclub said:

I pulled a TPS apart a few months back, it basically does the same job as your APPS except it sits on the throttle body.  Inside were fine bent metal arms rubbing on a set of carbon tracks that curved around a plastic disc. Obviously the first few mm get rubbed a lot, while the full throttle end of the tracks never gets touched. I expect you've rubbed the first mm or two away over the years, so on  a stock computer it is a throwaway, or at least a custom throttle stop job.

You could-

-Stop the throttle going all the way back to zero, although I expect there is an idle switch in there to tell the ECU to idle, and if you stop the pedal in front of that short contact the ECU will not know it is at idle. You might steal 2 or 3mm of pedal and still get idle. You would need a bolt on the floor to stop it returning all the way, something you could adjust.

-Study yours with a multi-meter and see exactly when it makes a circuit. Then head for a wrecker and search for one that switches on earlier. I expect most old Corollas suffer the same problem.

The Haltech ECU I fitted recently asks you to click on a computer when you have zero throttle, and again when you are holding full throttle, so Haltech don't worry about where the pedal is in reality, they set the ECU up according to where you want idle. Sadly I doubt a Toyota ECU can do that.

 

Hi Altezzaclub,

Thank you for your detailed advice. However, this sensor type is brushless (Hall effect) and not a potentiometer (carbon tracks with a metal brush, and the like). Additionally, there is no such thing as an "idle switch" either. Here is the picture from when I disassembled it.

Cheers,

 

Hi Dananjaya,

                       Yep, a bit more complicated than the olde days, when there was a simple cable between accelerator pedal, & the throttle body.

This following link, has a good description, of how they work, & also describes the one like yours, with Hall Effect switches, which do away, with the need for resistance & wiper brushes.

https://premierautotrade.com.au/news/accelerator-pedal-position-sensors.php

Enjoy !

Cheers Banjo

Edited October 24, 20241 yr by Banjo