P1128, JEEP, DODGE, MITSUBISHI, CHRYSLER: CLOSED-LOOP FUELING NOT ACHIEVED BANK 1
POST UPDATED IN May, 2023
P1128, JEEP, DODGE, MITSUBISHI, CHRYSLER: CLOSED-LOOP FUELING NOT ACHIEVED BANK 1
Fuel management systems are used to maintain and regulate engine fuel consumption. The design of these systems allows the measurement and the effective control of the fuel and consequently of the engine.
When the system works in a closed circuit, it is the Oxygen Sensor that is used for feedback control. The PCM (Powertrain Control Module) uses the input from these sensors to carry out the regulation of the fuel mixture, it is also known as the fuel feedback control circuit. The PCM relies on these signals and in response changes the fuel mixture. This process is known as a closed-loop since the PCM uses the sensor input to regulate the mixture, resulting in a round trip from rich to poor, achieving greater efficiency of the catalytic converter.
An open circuit is a condition in which no signal is received from the O2 Sensor, such as when the engine is started when it is cold. In these cases, the PCM gives the command for a fixed rich (immutable) fuel mixture. In case the Powertrain Control Module detects a condition where the vehicle has been running in open circuit, from the start of engine for more than a calibrated time, when the conditions required closed-circuit operation, the fault code P1128 OBDII will be set.
The reasons why the diagnostic code P1128 OBD2 is set are
To solve the DTC code P1128 OBDII consider the following: