Express 1/2 Ton Van V8-5.7L VIN R (1999)
Camshaft Position Sensor: Adjustments
TEST PROCEDURE
The ignition timing cannot be adjusted. The distributor may need adjusting to prevent crossfire. To insure proper alignment of the distributor, perform
the following:
1. With the ignition OFF, connect the scan tool.
2. Start the engine. Allow the engine to idle until the engine reaches normal operating temperature.
IMPORTANT: Cam Retard Offset reading will not be accurate below 1,000 RPM.
3. Increase engine speed to 1000 RPM while performing the following steps.
4. Use the scan tool in order to monitor the Cam Retard Offset.
5. If the Cam Retard indicates a value of 0 degrees, the distributor is properly adjusted.
6. If the Cam Retard does not indicate 0 degrees, the distributor must be adjusted.
ADJUSTING PROCEDURE
1. With the engine OFF, slightly loosen the distributor hold down bolt.
IMPORTANT: Cam Retard Offset reading will not be accurate below 1000 RPM.
2. Start the engine and raise the engine speed to 1000 RPM.
3. Use the scan tool in order to monitor the Cam Retard Offset.
4. Rotate the distributor as follows:
^
To compensate for a negative reading, rotate the distributor in the counterclockwise direction.
^
To compensate for a positive reading, rotate the distributor in the clockwise direction.
5. Repeat step 4 until 0 degrees is obtained.
6. Turn OFF the ignition.
NOTE: Refer to Fastener Notice in Service Precautions.
7. Tighten the distributor hold-down bolt.
Tighten
Tighten the bolt to 3 N.m (25 lb ft)
8. Start the engine.
9. Raise the engine speed to 1000 RPM and view the Camshaft Retard Offset.
