P1121 code, tried a few things but nothing! Help!
08-26-12, 04:54 PM
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P1121 code, tried a few things but nothing! Help!
I was driving on the freeway and all of a sudden I had a "loss" of power. In order to accelerate I had to put the pedal all the way in. Engine light came on so I drove back home and scanned the code. It ended up being P1121 which is "Accelerator pedal position sensor range/performance problem." The problem seems to happen when the car is warm; when cold it drives like it should. I did a search on here and found some things that people recommended doing in order to fix the problem, here's what I've done.
-Cleaned the MAF Sensor with CARB cleaner
-Clean intake
-Cleaned all sensor contacts TBS, MAF, etc.
-Changed Air Filter
-Reset ECU Via EFI fuse
However, I did notice this (pics below). Am I supposed to have that much slack? Or is that something that's controlled by some other component? Why is the problem only occuring once the engine is warm?
What part should I start replacing?
-Cleaned the MAF Sensor with CARB cleaner
-Clean intake
-Cleaned all sensor contacts TBS, MAF, etc.
-Changed Air Filter
-Reset ECU Via EFI fuse
However, I did notice this (pics below). Am I supposed to have that much slack? Or is that something that's controlled by some other component? Why is the problem only occuring once the engine is warm?
What part should I start replacing?
08-27-12, 02:24 PM
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Anyone?
By the way, I recorded a video of something I noticed (sorry for the honking and upside down video). Pardon my ignorance but is that normal? Isn't the flap supposed to open completely when pushed all the way around? Could this be what's causing the problem?
By the way, I recorded a video of something I noticed (sorry for the honking and upside down video). Pardon my ignorance but is that normal? Isn't the flap supposed to open completely when pushed all the way around? Could this be what's causing the problem?
08-27-12, 04:23 PM
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Just tested the resistances on the Throttle Control Motor, Throttle Position Sensor and Accelerator Pedal Sensor and all check out within range.
I also cleaned the Throttle Position Sensor but still have the problem.
Weird thing is that when re-sitting the TPS I would notice that it would fix the problem and as soon as I would drive out of my driveway the problem would come back. I'm puzzled, hoping someone can suggest what part to start replacing first.
I also cleaned the Throttle Position Sensor but still have the problem.
Weird thing is that when re-sitting the TPS I would notice that it would fix the problem and as soon as I would drive out of my driveway the problem would come back. I'm puzzled, hoping someone can suggest what part to start replacing first.
08-27-12, 07:04 PM
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Another engine code just popped up: P1128 Throttle Control Motor Malfunction
Might need to replace the motor, if that doesn't work then maybe the APPS.
08-27-12, 07:47 PM
#6
http://forum.ih8mud.com/100-series-c...-problems.html
A LOT of info here. Try replacing the APPS. It is kinda pricey though..what kind of Lexus is the patient here? it also could be your EGR malfunctioning.
Cheers
A LOT of info here. Try replacing the APPS. It is kinda pricey though..what kind of Lexus is the patient here? it also could be your EGR malfunctioning.
Cheers
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08-27-12, 08:50 PM
#8
You can adjust the slack on your throttle cable by loosing the nut and just tightening it. As far as the APPS i know what your going thru. I went thru and stiil is going thru the same problem. I was getting the code swapped out the APPS sensor and a month later im getting the code again. Its annoying and sucks when your driving because at any given time you can loose throttle. Its better and cheaper to just buy a used TB with all the sensors then just replacing the APPS. Also what was your voltage when you checked the Throttle Control Motor, Throttle Position Sensor and Accelerator Pedal Sensor
08-28-12, 09:36 AM
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You can adjust the slack on your throttle cable by loosing the nut and just tightening it. As far as the APPS i know what your going thru. I went thru and stiil is going thru the same problem. I was getting the code swapped out the APPS sensor and a month later im getting the code again. Its annoying and sucks when your driving because at any given time you can loose throttle. Its better and cheaper to just buy a used TB with all the sensors then just replacing the APPS. Also what was your voltage when you checked the Throttle Control Motor, Throttle Position Sensor and Accelerator Pedal Sensor
How do you check the voltage on all of the sensors? I checked all the resistances but not the voltage. Do I do this with the ignition on or when completely off?
Also, can you guys do me a favor? Is this how the Throttle Control Motor is supposed to sound when the ignition is on and you rotate the APPS? The manual says to listen to any whining or friction noise which can usually mean the Throttle Control Motor is bad. I'm not sure if you consider this whining. Listen:
I've got it down to two parts that can be the culprits, APPS and TCM but each is $250!!! So I'm trying to make the best judgement on which is most likely.
08-28-12, 11:32 AM
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09-01-12, 03:41 PM
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Glad to see a recent post on this. I'm having the same issue on the GFs 2001 is300. It happened all of a sudden when she was trying to pass on a hill, car lost all power. I scanned the car initially and got P1120, P1121, P0171, and P0174. I took the car out and drove it and it was definitely stumbling, and surging on / off when trying to accelerate. I cleared the codes and drove around a little more. It took a while and a few warm up cycles before I could duplicate the issue again. The second time, I only got the p1121 code, so I'm leaning more towards the accelerator pedal position sensor. Is there a difference between the throttle position sensor and the accelerator pedal position sensor from those pdfs? I'm thinking about just replacing the sensor really quick.
09-01-12, 03:47 PM
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Forgot to add that I did a visual inspection of the wires, throttle body, etc. Cleaned the MAF with MAF spray checked the air filter, checked for vacuum leaks, etc.
Also the CEL is on solid, not flashing. In the past on other cars I've worked on when the CEL flashes its usually indicating a misfire. The TRAC OFF light flashes and so does the ABS light. But the ABS light only flashes when the car is not moving which I thought was kind of odd. At a stop with the car in D or N the ABS light flashes. As soon as the car starts moving it turns off
Also the CEL is on solid, not flashing. In the past on other cars I've worked on when the CEL flashes its usually indicating a misfire. The TRAC OFF light flashes and so does the ABS light. But the ABS light only flashes when the car is not moving which I thought was kind of odd. At a stop with the car in D or N the ABS light flashes. As soon as the car starts moving it turns off