P0132

Diagnostic Chart:

Wiring Diagram:

Circuit Description

The Powertrain Control Module (PCM) supplies a voltage of about 0.45 volt between terminals C2-22 and C2-21 (if measured with a 10 megohm digital voltmeter, this may read as low as 0.32 volt). The Oxygen Sensor (O2S 1) varies the voltage within a range of about 1 volt if the exhaust is rich, down through about 0.10 volt if the exhaust is lean.

The sensor is like an open circuit and produces no voltage when it is below 315°C (600°F). An open sensor circuit or cold sensor causes Open Loop operation.

If 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, it must have a clean air reference provided to it. This clean air reference is obtained by way of the oxygen sensor wire(s). Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air reference and degrade oxygen sensor performance.

Conditions for Setting the DTC

^ DTCs P0106, P0107, P0112, P0113, P0117, P0118, P0121, P0122, P0123, P0200, P0300, P0301, P0302, P0303, P0304, P0404, P0405, P0506, P0507, P1404, P1441 not set.

^ Engine run time is greater than 25 seconds.

^ Engine Coolant Temperature (ECT) is greater than 70°C (158°F).

^ Air/fuel ratio is between 14.5:1 and 14.7:1.

^ Engine is operating in Closed Loop.

^ Throttle Position (TP) angle is between 5% and 50%.

^ Engine has met the above conditions for 30 seconds.

^ O2S 1 voltage is greater than 945 mV for 50 seconds.

Or

^ O2S 1 voltage is greater than 1042 mV for 50 seconds while in deceleration mode.

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.

^ Coolant fan turns ON.

^ Vehicle will operate in Open Loop.

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.

^ DTC(s) can be cleared by using the scan tool.

Diagnostic Aids

The DTC P0132 or rich exhaust is most likely caused by one of the following items:

^ Fuel pressure - The system will go rich if fuel pressure is to high. The PCM can compensate for some increase, however, if it gets too high, a DTC P0132 will be set. Refer to Fuel System Diagnosis. System Diagnosis - Fuel System

^ Leaking injector - A leaking or malfunctioning injector can cause the system to go rich causing a DTC P0132. Refer to Fuel Injector Coil Test.

^ Electronic Ignition (EI) shielding - An open Ignition Control Module (ICM) reference low 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 TCC 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 O2S 1 for silicone contamination from fuel or use of improper RTV sealant. The sensor 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.

Test Description

Number(s) below refer to the step number(s) on the Diagnostic Table.

1. The Powertrain OBD System Check prompts the technician to complete some basic checks and store the freeze frame and failure records data on the scan tool if applicable. This creates an electronic copy of the data taken when the malfunction occurred. The information is then stored in the scan tool for later reference.

2. This step determines if DTC P0132 is the result of a hard failure or an intermittent condition. It may be necessary to operate the vehicle within the Freeze Frame conditions and Conditions for Setting the DTC in order to duplicate the malfunction detected by the PCM.

4. This step simulates a DTC P0131. If the PCM senses the change, the PCM and wiring are OK.

6. The replacement PCM must be programmed and the crankshaft position system variation procedure must be preformed. Refer to the latest Techline procedure for PCM reprogramming and also refer to Powertrain Control Module for the Crankshaft Position System Variation Procedure.

8. If no malfunctions have been found at this point and no additional DTCs were set, refer to Diagnostic Aids for additional checks and information.