Obd2 codes po121 will not clear

po121 is throttle position sensor is out of range.po442 is emissions system leak detected small leak.po455 is same as po442 but large leak.po496 is high purge flow . Check all the vacuum lines plastic also cause one of them is broken.

code p0121 refers to throttle position (TP)switch A/ pedal position (AAP) switch A-range/performance problem===causes --accelerator cable adjustment--TP/APP switch
PO121 also refers to TP sensor A/ accelerator pedal position AAP switch A -range / performance problem===causes --accelerator cable adjustment. TP/AAP sensor --wiring
Cheapest first is to check the cable adjustment then the cheapest part after that .

It requires that you use a scanner. Try this clean throttle body with a good throttle body and tooth brush. I unbolt the throttle body and remove the studs from the intake that way u don\'t have to remove the coolant hoses from the throttle body.clean all the black goop off the plate and the inside of the body. Clear codes reassemble and start

P0121 Throttle/Pedal Position Sensor/Switch A Circuit Range/Performance Problem
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car ecu repair tool

it is on the thottle body

If you go to a local autozone, they will scan/clear ODB2 codes on your vehicle for free.

Hi

Please check the link to get a detailed idea about the code:-

http://www.obd-codes.com/p0421

Please get back to us if you have further query else please accept the suggestion.
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PO121 is a throttle position sensor problem. I would be checking that if it stalls when you come to a stop sign and stuff like that.

I have a 2003 new beetle TDI. I have got error codes on my ECM that have stopped my engine from starting. I got an OBD2 reader from the auto parts store. I plugged it into the OBD2 port below the steering wheel and got the error codes. After writing them down, I cleared the codes. the car started fine. It has pulled this a couple times over three years. I carry an OBD2 reader with me so I can clear the codes and get going again. Good Luck

po121 means that there is a problem with the throttle position sensor ( tps). or in the wiring or connector, most likely its the tps that is bad. first remove connection from tps, heres how to test. use an ohms meter and hook a lead to top or bottom terminal of tps. use other probe on center terminal of tps. move throttle plate slowly, if the needle on meter does not move at a smooth pace, then tps is bad. good-luck!!