← Back to list

1996 Chevy K1500 1/2 Ton P0122 Code After Transmission Rebuild - TPS Issue

Model: 1996 Chevy K1500 1/2 ton Fault Code: P0122 Posted: 2012-01-27 15:51

I recently had my 1996 Chevrolet K1500 1/2-ton truck completed with a transmission rebuild. Prior to the work, I was experiencing two diagnostic trouble codes: an EGR valve issue and a P0122 code related to the throttle position sensor (TPS). After checking the voltage input to the TPS while the engine is off, I observed 5 volts — which is within normal range. I replaced the TPS with a new unit and cleared the P0122 code using an OBD-II scan tool. However, the code reappeared after approximately 10 miles of driving. The truck now shows the same P0122 error despite the replacement. I'm at a loss as to what might be causing this issue. Any insights or troubleshooting steps for this specific model and year would be greatly appreciated.

Related fault codes

P0122

Comments (5)

Anonymous 2012-01-29 08:05

Has the EGR code disappeared since the transmission work? If so, that's a positive sign.

Anonymous 2012-01-31 18:20

The EGR-related code is now gone — which suggests the transmission rebuild didn't affect that system.

Anonymous 2012-01-31 20:20

Were there any P0122 or other codes present before the transmission was rebuilt? This helps determine if the issue originated from the repair.

Anonymous 2012-01-31 22:48

I once had a random misfire code (P1351) that turned out to be caused by a faulty fuel injection system. After replacing the MPI system, the codes disappeared — and I noticed no issues after the transmission was installed in my truck. This may suggest a connection between engine components and post-rebuild diagnostics.

Anonymous 2012-02-01 06:17

What brand of TPS did you install? A live data read or scope capture of the sensor's signal sweep could help identify if the issue is with the sensor itself or its wiring. Also, which engine type (e.g., 4.3L V6) does your truck have? This information can be critical for accurate diagnosis.