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goodwrench9124, ASE Certified Technician
Category: Chevy
Satisfied Customers: 3432
Experience:  Ase Master Certified, GM Master Certified Tech. Awarded GM Top performer, Hybrid certified
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I have a check engine code po122 sensor A low imput whats it

Customer Question

I have a check engine code po122 sensor A low imput whats it mean and how bad is it code is for a 1998 chvey malibu
Submitted: 7 years ago.
Category: Chevy
Expert:  goodwrench9124 replied 7 years ago.
Hello, and welcome. what year of malibu do you have? and what engine size do you have?
Customer: replied 7 years ago.
1998 2.4l
Expert:  goodwrench9124 replied 7 years ago.

ok, this code indicates a problem with the throttle position sensor mounted on the throttle body.The Powertrain Control Module (PCM) supplies a 5.0 volt reference signal and a ground to the sensor. The TP sensor sends a voltage signal back to the PCM relative to the throttle plate opening. The voltage will vary from approximately 0.35 volt at closed throttle, to over 4.65 volts at wide open throttle (WOT). without a scan tool that reads real time data it would be hard to know for sure what the problem is. but 90 percent of the time it is the tps sensor that is causing the problem. here is a picture, fairly easy to replace.


If there is anything you dont understand, please feel free to ask me to explain.

tps is number 2 in below picture



Customer: replied 7 years ago.
will this problem cause the car to shift hard at times it comes and gos
Expert:  goodwrench9124 replied 7 years ago.
yes it will. this sensor tells the engine control module what position you are pushing the throttle so it will no how much fuel to spray into engine and what speed to shift the transmission. your symtons are classic problems that occur with a bad tps sensor.
goodwrench9124 and 2 other Chevy Specialists are ready to help you
Customer: replied 7 years ago.
thank you for your answer
Expert:  goodwrench9124 replied 7 years ago.

You are very welcome!!!


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