NOTE: This message was sent thru a mail2news gateway. No effort was made to verify the identity of the sender.
--------------------------------------------------------
This is on 5.7L TBI Caprice with OBD-I. Check Engine Light came on, I pulled the codes and got:
13: Oxygen Sensor Circuit Check for a sticking or misadjusted TPS. Check wiring to O2 Sensor. Replace O2 Sensor.43: ESC (Electronic Spark Control) The ESC retard signal has been on for too long or the system has failed a functional check.
54: Fuel Pump Low Fuel Pump voltage. Sets when the fuel pump voltage is less than 2 volts when reference pulses are being received.First, I replaced O2 sensor recently. Secondly, acceleration is erratic. Sometimes very good like it should be with this 9C1 engine and sometimes cannot go beyond 55 on a hill and today I think it went into limp mode because I couldn't go beyond 25. This points to a bad knock sensor. However, code 43 could also be ESC (Electronic Spark Control). Which one is it?
So where do I start? With the ESC, knock sensor or the fuel pump and are these related or different issues? Is code 13 merely a side effect of bad knock sensor/ESC?