See Figure 1
The Powertrain Control Module (PCM) performs many functions on your vehicle. The module accepts information from various engine sensors and computes the required fuel flow rate necessary to maintain the correct amount of air/fuel ratio throughout the entire engine operational range.
Based on the information that is received and programmed into the PCM's memory, the PCM generates output signals to control relays, actuators and solenoids. The PCM also sends out a command to the fuel injectors that meters the appropriate quantity of fuel. The module automatically senses and compensates for any changes in altitude when driving your vehicle.
REMOVAL & INSTALLATION
See Figure 2
When the battery has been disconnected, some abnormal driving symptoms may occur while the PCM relearns its fuel trim. The vehicle may need to be driven 10 miles (16 km) or more to relearn the fuel trim.
- Disconnect the negative battery cable.
- Remove the power steering fluid reservoir from its mount (without disconnecting the fluid lines), and position it out of the way.
- Loosen the PCM harness connector retaining bolt.
- Remove the engine harness connector from the PCM.
- Lower the glove box door.
- From inside the vehicle, remove the nut on the PCM support bracket and remove the bracket.
- Remove the PCM.
- Position the PCM into place.
- Install the PCM support bracket and tighten the nut to 24-32 inch lbs. (3-4 Nm).
- Reposition the glove box door.
- Install the PCM harness connector and tighten the bolt to 32 inch lbs. (4 Nm).
- Position the power steering fluid reservoir and tighten the retaining bolts.
- Connect the negative battery cable.