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Step C - Perform A/F Sensor Test

Step C: Perform A/F Sensor Test

1. Use CONSULT-II DATA MONITOR to view;

^ Engine Speed, and





^ A/F Sensor voltage (see Figure 2).

2. Hold the engine speed at about 2000 rpm no-load for 2 minutes.

^ This will create a stable condition for step 3 (below).

3. Observe A/F SEN1 (B1) and A/F SEN1 (B2) voltage for 30 seconds while holding 2000 rpm no-load.

a. A/F sensor voltages should remain (most of the time) between 1.37 and 1.57 volts.

^ If the engine rpm is held constant, voltage will fluctuate, but should remain in this range.

b. If, most of the time, the A/F sensor voltages are out of this range:

^ The vehicle has an additional incident.

^ This bulletin does not have repair information for an A/F Sensor or Fuel Management System incident.

^ Use the appropriate Service Manual (ESM), section EC (P1031/P1051/P1148/P1168), to further diagnosis and repair the additional incident.