Fuel Trim Monitor
This monitor applies to DTCs P0171, P0172, P0174, and P0175. Following conditions must be met during the test:
- Engine Coolant Temperature Is 176-207°F (80-97°C)
- Atmospheric Temperature Is 14-140°F (-10-60°C)
- Selector Lever Is In "D" Range
NOTE:
Remove all test equipment from vehicle and install all components and connectors that were removed or disconnected during testing.
Monitor takes about 35 minutes to complete. To run monitor, use illustration. See Fig 1 . This monitor must be performed twice. Perform steps as follows:
- Start the engine and allow it to reach 176°F (80°C).
- Accelerate vehicle to 55-60 MPH.
- Drive at 55-60 MPH for 30 minutes or more (5th gear on M/T). During this period DO NOT drive at constant speed for more than 120 seconds. Carry out one gradual deceleration and acceleration, returning to a vehicle speed of 55-60 MPH within a 120 second time frame (this is when monitor runs).
- Return vehicle to shop and turn ignition switch to LOCK position.
- Recheck for DTCs. If DTC P0171, P0172, P0744 or P0175 resets, return to appropriate diagnostic procedure under DIAGNOSTIC TESTS .