Road Test
Road Test1. Note battery voltage. Low voltage can cause PCM powerup and initialization problems. Battery voltage should be no lower than 11.5 volts for satisfactory operation.
2. Connect scan tool to diagnostic link connector. Set tool to record fault codes, or have helper use tool to interrogate system during test.
3. Start engine and check idle operation. Note any faults such as rough idle, stalling, excessive smoke.
4. Apply service brake and shift transmission into drive range. Note if engine stalls, runs rough, or another fault occurs.
5. Drive vehicle on road at posted limits. Note operation under light and heavy acceleration, and at normal cruise speeds. Note faults such as surge, miss, vibration, noise, low power, smoke (blue, black, white).
6. Shift into neutral at cruise speed and note engine operation. If vibration or noise was experienced but it now stops, problem may be with drive belt, engine mount, accessory, U-joint, or torque converter.
7. Return to shop and note fault codes recorded by PCM . If a fuel system fault was noted during road test, refer to diagnosis charts, perform fuel system tests, and check system electrical components with scan tool.