Question

My 04 chevy trail blazer is coming up with these codes P2135 P2138 and P0641 can you help me out I have already changed the throttle position sensor and the acceleration pedal

Answer 1

P0641 5 volts refference circuit

P2135 TP sensor 1 and TP sensor 2 exceeds a predetermined value

P2138 APP sensor 1 and APP sensor 2 exceeds a predetermined value

The fix here is resolve the code that is set P0641 , this is the 5 volts refference to Throttle position sensor, APP sensor, Engine cooling fan speed sensor, A/C pressure sensor ,fuel tank pressure sensor , oil pressure sensor. What happens when you set a P0641 one of these component affected the 5 volts refference in return you set a P2135 and P2138 , then it goes to limp home mode. Vehicles are built by robots, in return there is a pattern failure for all make and models. suspect the cooling fan speed sensor, , what happens is the wire at the cooling fan tends to chaff and there cooling poor  performance, in return the engine  accelerates differently without setting a throttle or APP code.  these are known condition with the trailblazer. , very rarely the problem is the oil pressure sensor .Suspect the cooling fan.