Accelerator Pedal Position Sensor?
Lead Lap
Joined: May 2008
Posts: 774
Likes: 1
From: california
Hey, sorry, didn't realize you had an earlier one.
Yours actually still has a throttle cable I believe, but only a partial cable - the throttle body still has a motor that operates the butterfly. Your pedal however doesn't have the sensor to the best of my knowledge.
Refer to the link below for part reference. Repace ******* with t o y o d i y (no spaces)
http://www.*******.com/parts/p_U_199...AQKA_7801.html
Yours actually still has a throttle cable I believe, but only a partial cable - the throttle body still has a motor that operates the butterfly. Your pedal however doesn't have the sensor to the best of my knowledge.
Refer to the link below for part reference. Repace ******* with t o y o d i y (no spaces)
http://www.*******.com/parts/p_U_199...AQKA_7801.html
So I ended up ordering a new Throttle Position Sensor (TPS), hopefully this solves the problem. Now the only thing is getting a diagnostic tool that can help me adjust it to the factory specs (14.4 - 16%). Do you guys think I'll be able to exactly mark the position of my old one and just install the new one in the same position? 
BTW, it's for a GS430, so there is no cable at all that needs to be adjusted, all electronic.
BTW, it's for a GS430, so there is no cable at all that needs to be adjusted, all electronic.
So I ended up ordering a new Throttle Position Sensor (TPS), hopefully this solves the problem. Now the only thing is getting a diagnostic tool that can help me adjust it to the factory specs (14.4 - 16%). Do you guys think I'll be able to exactly mark the position of my old one and just install the new one in the same position?
BTW, it's for a GS430, so there is no cable at all that needs to be adjusted, all electronic.
BTW, it's for a GS430, so there is no cable at all that needs to be adjusted, all electronic.
Thread Starter
Driver School Candidate
Joined: Aug 2009
Posts: 29
Likes: 0
From: AZ
So, here is our latest with this ongoing headache. After having put on 4 new tires, we had the dealer do the 4-wheel alignment. While there, my wife let them know we are still experiencing the "loss of power" in the pedal after taking off from a stop as well as occasionally while cruising on the highway. Having already replaced the plugs, MAF sensor, and TPS, the only thing left in my mind was the Accelerator Pedal Position Sensor.
The (Parts Specialist) tells her the whole pedal assembly would need to be changed, not just a sensor. Part is $215, not including labor. However, the Parts Specialist also said the more likely culprit is the the whole throttle body and that he has not seen many APPS go bad. Cost of the throttle body assembly is $800 without labor.
Looking for honest opinions here, but do you think the throttle body itself could be causing the issue to arise again? I know it has been cleaned recently. Is it worth spending the money to just have it done, or starting out with the cheaper sensor and see how long that lasts if it is not the issue?
For now, she just has to deal with it and hope it doesn't end up causing some serious accident or keep her from avoiding one as these huge labor costs every month are hard to come up with.
The (Parts Specialist) tells her the whole pedal assembly would need to be changed, not just a sensor. Part is $215, not including labor. However, the Parts Specialist also said the more likely culprit is the the whole throttle body and that he has not seen many APPS go bad. Cost of the throttle body assembly is $800 without labor.
Looking for honest opinions here, but do you think the throttle body itself could be causing the issue to arise again? I know it has been cleaned recently. Is it worth spending the money to just have it done, or starting out with the cheaper sensor and see how long that lasts if it is not the issue?
For now, she just has to deal with it and hope it doesn't end up causing some serious accident or keep her from avoiding one as these huge labor costs every month are hard to come up with.
So, here is our latest with this ongoing headache. After having put on 4 new tires, we had the dealer do the 4-wheel alignment. While there, my wife let them know we are still experiencing the "loss of power" in the pedal after taking off from a stop as well as occasionally while cruising on the highway. Having already replaced the plugs, MAF sensor, and TPS, the only thing left in my mind was the Accelerator Pedal Position Sensor.
The (Parts Specialist) tells her the whole pedal assembly would need to be changed, not just a sensor. Part is $215, not including labor. However, the Parts Specialist also said the more likely culprit is the the whole throttle body and that he has not seen many APPS go bad. Cost of the throttle body assembly is $800 without labor.
Looking for honest opinions here, but do you think the throttle body itself could be causing the issue to arise again? I know it has been cleaned recently. Is it worth spending the money to just have it done, or starting out with the cheaper sensor and see how long that lasts if it is not the issue?
For now, she just has to deal with it and hope it doesn't end up causing some serious accident or keep her from avoiding one as these huge labor costs every month are hard to come up with.
The (Parts Specialist) tells her the whole pedal assembly would need to be changed, not just a sensor. Part is $215, not including labor. However, the Parts Specialist also said the more likely culprit is the the whole throttle body and that he has not seen many APPS go bad. Cost of the throttle body assembly is $800 without labor.
Looking for honest opinions here, but do you think the throttle body itself could be causing the issue to arise again? I know it has been cleaned recently. Is it worth spending the money to just have it done, or starting out with the cheaper sensor and see how long that lasts if it is not the issue?
For now, she just has to deal with it and hope it doesn't end up causing some serious accident or keep her from avoiding one as these huge labor costs every month are hard to come up with.
I'd still say its your APPS sensor. I've replaced mine when I had similar issues and its perfect now. You can find the part a lot cheaper and the install is super easy.
For anyone who is still having this problem, I was getting the usual P1121 error code and loss of power. I changed the TPS, didn't fix the problem. Like Och said, the thing that finally fixed it was the APPS, I just ordered the entire accelerator pedal assembly w/ sensor from Sewell. Don't waste your time and money on changing unnecessary parts like the TPS.
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Instructor
Joined: Feb 2002
Posts: 793
Likes: 63
From: California
I am having the same problem since 2002 and have just lived with it until it has progressively gotten worse.
I have a 2000 GS 300.
It has not thrown any codes but I cleaned the MAF and it seems to help a bit. I am crossing my finger that is all I need to do. Did anyone else repair their ECU? If so where? and what needs to be repaired in it?
FOr those of you looking for parts check out my research so far. Please post part numbers for Pedal sensor
MAF
http://shop.advanceautoparts.com/web...GRPSENSAMS____
PCV Valve
http://shop.advanceautoparts.com/web...GRPFILTAMS____
I think this is the throttle positional sensor everyone is talking about. (someone please confirm)
http://shop.advanceautoparts.com/web...GRPSENSAMS____
Advance Auto Parts has a bunch codes...
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Advance Auto Website
free shipping if your order is over $50. For free shipping items, you can try this out:
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I have a 2000 GS 300.
It has not thrown any codes but I cleaned the MAF and it seems to help a bit. I am crossing my finger that is all I need to do. Did anyone else repair their ECU? If so where? and what needs to be repaired in it?
FOr those of you looking for parts check out my research so far. Please post part numbers for Pedal sensor
MAF
http://shop.advanceautoparts.com/web...GRPSENSAMS____
PCV Valve
http://shop.advanceautoparts.com/web...GRPFILTAMS____
I think this is the throttle positional sensor everyone is talking about. (someone please confirm)
http://shop.advanceautoparts.com/web...GRPSENSAMS____
Advance Auto Parts has a bunch codes...
15% off all Orders $100+, Get a $50 off $100 Coupon on a future order Coupon Code: JN15
20% off all Orders Coupon Code: [COUPON=25637][COUPON=25638]P20[/COUPON][/COUPON]
$10 off $30, $20 off $50, $30 off $100+ Coupon Code: A123
$50 off $150 Coupon Code: VISA
$20 off $75+ Coupon Code: BIG20
$25 off $60+ Coupon Code: BIG25
$30 off $75+ Coupon Code: BIG30
$35 of $85+ Coupon Code: BIG35
$50 off $200+ Coupon Code: BIG50
20% off All Orders Coupon Code: P20
Advance Auto Website
free shipping if your order is over $50. For free shipping items, you can try this out:
http://www.superfillers.com/index.ph...vanceautoparts
Rookie
Joined: Oct 2007
Posts: 68
Likes: 0
From: South Carolina
For anyone with a GS 400. If you get a P1121 code by itself. It is most definitely your acceleration position sensor that is going bad. I've done extensive research within the past month and everyone who had this code replaced that sensor. Also I replaced mines today and my car is riding perfect.
Last edited by Trouble-T; Jun 13, 2011 at 08:09 PM. Reason: error
Instructor
Joined: Feb 2002
Posts: 793
Likes: 63
From: California
For anyone with a GS 400. If you get a P1121 code by itself. It is most definitely your acceleration position sensor that is going bad. I've done extensive research within the past month and everyone who had this code replaced that sensor. Also I replaced mines today and my car is riding perfect.
Whats the cost?
Instructor
Joined: Feb 2002
Posts: 793
Likes: 63
From: California
It seems like I FIXED MY PROBLEM..
As stated in previous posts. I was having the delay but no codes.
I changed the MAF (no results)
I changed the PVC valve (no results)
I finally decided it was time to CLEAN the throttle body. After I removed the throttle body I figured I would do the spark plugs.
After removing everything to get to the spark plugs I noticed there was a significant amount of oil that leaked from the valve cover into the space of the spark plugs.
I never noticed this because the valve cover was not leaking on the outside area where it was easily seen. I replaced the valve cover gaskets and the spark plug as well as cleaned the throttle body. I went ahead and tighten the accerlator cable as well.
Since then (5 days now) it has been perfect. NO problems yet.
Will let you guys know if it comes back.
As stated in previous posts. I was having the delay but no codes.
I changed the MAF (no results)
I changed the PVC valve (no results)
I finally decided it was time to CLEAN the throttle body. After I removed the throttle body I figured I would do the spark plugs.
After removing everything to get to the spark plugs I noticed there was a significant amount of oil that leaked from the valve cover into the space of the spark plugs.
I never noticed this because the valve cover was not leaking on the outside area where it was easily seen. I replaced the valve cover gaskets and the spark plug as well as cleaned the throttle body. I went ahead and tighten the accerlator cable as well.
Since then (5 days now) it has been perfect. NO problems yet.
Will let you guys know if it comes back.
The throttle body plate is motor operated, and if the motor is bad, then yes, you will need a new throttle body. But then if the motor is bad, the problem should be getting more and more persistent, and eventually the motor would die completely and you wont be able to accelerate at all.
I'd still say its your APPS sensor. I've replaced mine when I had similar issues and its perfect now. You can find the part a lot cheaper and the install is super easy.
I'd still say its your APPS sensor. I've replaced mine when I had similar issues and its perfect now. You can find the part a lot cheaper and the install is super easy.
Driver School Candidate
Joined: Apr 2008
Posts: 19
Likes: 0
From: OK
My 430 is hesitating too. Espcially first thingin the morning. When I put it in reverse and just press the gas, it bogs then surges. I cleaned the throttle body, and that seemed to help the fading when driving constant 45mph. New MAF sensor didn't do anything, nor new air filter. No codes being thrown.