You probably don't have a bad TPS, the engine ECU will store a closed throttle voltage value after the engine is started for the first time with cleared memory. If the throttle stop is not adjusted right or the butterfly is not returning to the same position every time the throttle is released the ECU will store a tps code. Check the throttle cable adjustment when the engine is running (due to the butterfly vacuum positioner) and make sure it's not too tight.