P0132

Oxygen Sensor 1 (O2S 1) Circuit:

Circuit Description
The Powertrain Control Module (PCM) supplies a voltage of about 0.45 to the Oxygen Sensor 1 (O2S 1). The O2S 1 voltage varies within a range of about 1 volt when the exhaust is rich, down to about 0.10 volt when the exhaust is lean.
The O2S 1 is like an open circuit and produces no voltage when it is below 315°C (600°F). An open O2S 1 circuit or cold sensor causes "Open Loop" operation.

Conditions For Setting The DTC
- When one or more of the following DTCs are not set P0107, P0108, P0112, P011 3, P0117, P0118, P0121, P0122, P0123, P0300, P0301, P0302, P0303, P0304, P0506, P0507, P1406, P1441.
- The engine coolant temperature is greater than 70°C (158°F)
- The TP angle is between 5% and 50%
- The Air/fuel ratio is between 14.5:1 and 14.7:1
- The engine is operating in "Closed Loop"
- The O2S 1 voltage is greater than 867 mV for 38 seconds

Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will illuminate.
- The PCM will record operating conditions at the time the diagnostic fails. This information will be stored in the Freeze Frame and Failure Records buffers.
- A history DTC is stored.

Conditions for Clearing the MIL/DTC
- The MIL will turn "OFF" after three consecutive ignition cycles in which the diagnostic runs without a fault.
- A history DTC will clear after 40 consecutive warm up cycles without a fault.
- DTCs can be cleared by using a scan tool.

Diagnostic Aids
DTC P0132 or rich exhaust is most likely caused by one of the following conditions:
- Fuel pressure - The system will go rich if the fuel pressure is to high. The PCM can compensate for some increase, however, if the fuel pressure gets too high, a DTC P0132 will set.
- Leaking injector - A leaking or faulty fuel injector can cause the system to go rich causing a DTC P0132.
- Electronic Ignition shielding - An Open ground circuit may result in EMI or induced electrical noise. The PCM looks at this noise as Crankshaft Position (CKP) sensor pulses. The additional pulses result in a higher than actual engine speed signal. The PCM then delivers too much fuel causing the system to go rich. The engine tachometer will also show higher than actual engine speed which can help in diagnosing this problem.
- MAP sensor - An output that causes the PCM to sense a higher than normal manifold pressure (low vacuum) can cause the system to go rich. Disconnecting the MAP sensor will allow the PCM to set a fixed value for the MAP sensor. Substitute a different MAP sensor if the rich condition is gone while the sensor is disconnected.
- Pressure regulator - Check for a leaking fuel pressure regulator diaphragm by checking for the presence of liquid fuel in the vacuum line to the regulator.
- TP sensor - An intermittent TP sensor output will cause the system to go rich due to a false indication of the engine accelerating.
- O2S 1 contamination - Inspect the O2S 1 for silicone contamination from fuel or use of improper RTV sealant. The O2S 1 may have a white powdery coating and result in a high but false voltage signal (rich exhaust indication). The PCM will then reduce the amount of fuel delivered to the engine causing a severe surge or driveability problem.

NOTE: Whenever the oxygen sensor pigtail wiring, connector or terminal are damaged, the entire oxygen sensor assembly must be replaced. DO NOT attempt to repair the wiring, connector or terminals. In order for the sensor to function properly, the O2S 1 must have a clean air reference. This clean air reference is obtained by way of the oxygen sensor wires. Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air reference and degrade the oxygen sensor's performance.

DTC P0132 - Oxygen Sensor (O2S) Circuit High Voltage Sensor 1:

Test Description
Numbers below refer to the Step numbers on the Diagnostic Table.
1. The OBD System Check prompts the Technician to complete some basic checks and store the Freeze Frame Data and the Failure records on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. This information on the scan tool can be referred to later.
9. Before replacing the PCM, check terminals for improper mating, broken locks, or physical damage to the wiring harness. Replacement PCM must be reprogrammed. Refer to the latest Techline information for programming procedures.