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i had a code come up this morning. it was twenty somthing degrees overnight and i got to work fine, but when i left for break the SES light came on and the car wouldnt shift until a higher rpm. the code i got was: P0122 TPS A Circuit Low Input. what do i need to do to fix the problem? please help....thanks. bye the way..its a 97 trans am LT1.
ok, cool.
TPS? Doesn't that stand for your Throttle Position Sensor? Sounds like its sending a weak signal to the PCM. You may need to replace the wires.
You can test the TPS. A chilton's manual will detail how. It's probably the sensor. It isnt the wires.
The code sets when the closed throttle TPS voltage is below 0.20V. You need to test the operation of the TPS, meauring the voltage between the blue wire and the black wire with the throttle closed (0.20-0.90V), rotate the throttle open slowly watching for a smooth voltage increase, and then at full throttle, should read about 4.0V higher than the closed throttle position. Also check to make sure you are getting 5.0V between the gray wire and the black wire at all times (key on).Quote:
Originally Posted by irishpenguin13
You need to find out why the voltage is so low at closed throttle. Could be a faulty sensor, may need adjustment ifs its on an aftermarket throttle body.
its a stock TB. im going to try replacing the TPS today. i'll let you know what happens. thanks for all the info.
I've seen tps sensors malfunction intemittently, so when you test it, it may show fine. I think you're on the right track replacing it. I've seen lots of them do this exact same thing.
yeah, i went through hell when i bought that BBK TB. i had to slot out the TPS till i got the right reading, but every time i nailed the throttle, it would throw it out of whack, SES light would come on, and it would shift like crap. its starting to act the same way with the stock TB on. it idles at like 1200 rpms in park sometimes. bla.