'00' SC400 code P0121 $1750 for repair?
 

Car went into "limp mode", happened to be a block from dealer. They chacked it out for free and told me its a code "P0121" Throttle Pedal Position Sensor. - Recommend Throttle motor Assy - $1750 installed.

For some reason that seems to be a bit rediculous. Does that sound like a rip off?

O Reillys has the sensor for $79, does that sound like the way to go?


Why would the dealer recommend a whole new throttle motor assy for $1750???
that seems so dirty to me...

What that's so crazy... I don't think Lexus would ever touch my car for that price, even a motor swap. My goodness. If the part from oriels has a warranty, then by all means. We are here to save money when we can!

$375 for the part from Lexus

$79 from Autozone

Why such a big difference???

Because some OEM parts are far more superior than aftermarket.

A new TPS from the dealer is actually around $80

^^^^^^ that price sounds correct from the dealer... if you decide to do this, mark the current tps and the intake itself and try to put the new one as close as possible. You will have to play with it to assure the idle and so on is close.

Hi, I read your thread about your similar problems, and I think I noticed, that you had a P1121 code, and that was the "acceleration sensor" ? or something like that. And mine is a P0121
which is the TPS I think.

Sounds like there are two sensors on either side of the throttle body. You mentioned the TPS should cost about $80. My dealer quoted $375. Perhaps he was quoting the wrong sensor?

Also since my code is the 0121 and not the 1121, that would indicate that I have the TPS problem, correct?

I also read that maybe the throttle body would need a cleaning from carbon build-up. In a quick answer, would that be a easy job for a semi skilled backyard mechanic, or does it require specialized skills?

thanks.

Oh, and lastly, can I clear these codes and restore engine function immediately with my coade reader? It does have an erase function...

Thanks for the help!!! It's just so disappointing that the car can become disabled like that, it could be a very dangerous situation to go limp in the middle of a heavy traffic situation..

Called the dealer back, and it's $107 for a TPS

When I asked why they wanted to install a whole complete Throttle Motor ASSY for $1750, she said that the code "P0121" didn't mean the sensor itself was bad, but rather that what it was measuring was bad...:sad:

So now I'm totally confused...

The $375 quote was most likely for the accelerator pedal sensor which is also on the throttle body. Yes, code 0121 is the throttle position sensor, it's an easy sensor to replace, just two bolts and a connector. The only hard part is calibrating it which requires a digital meter.

I recommend that you first erase the code with your reader and see if the check engine light comes on again, if it comes on again with the same code, replace the TPS.

Sorry if I missed it, but didn't sluggo42 say the Throttle PEDAL position sensor? Not the throttle position sensor..correct me if I'm wrong.

Yes, I did say throttle Pedal position sensor code P0121 I don't have a code list, and am going on what the Lexus tech wrote. Is that another different sensor apart from the TPS??

Good Grief!, how many sensors are there ???

P0121 is a Throttle Position Sensor Circuit Range/Performance Fault not throttle pedal position..P1121 is the Accelerator Pedal Position Sensor Circuit Malfunction..i have the diagnostic codes right in front of me

Hmm, does that sound then that perhaps I DO need a new throttle motor assy, rather than a TPS ?

I wonder if it could be getting that reading from a dirty throttle body? Why does it wait 2 months between failures? Wouldn't that be a constant problem?

With the dealer asking $1350 just for the part, I wonder if I can get it somewhere else for much less, and install myself?

My suggestion is to find a good local mechanic that you have a good relationship with and purchase a part from Lexus for the 375 and then have them install it it shouldn't be more than 3 to 4 hours of labor and between the part and the labor should cost you way less than one third of what the Lexus dealer is trying to charge you.

I've been doing this for years, only problem is theyre a little bit slow getting the car back to me.


Cleaning the throttle body is a good idea every few years.

The sensor would not got bad from a dirty throttle body, it just went bad or going bad from age like most electronics.