1977-78 Models: 810
- Make sure wiring and vacuum hoses are properly connected and that distributor is working properly. Connect timing light to engine. With engine warm, adjust engine speed to 2500-2800 RPM.
- Depress clutch pedal to disengage clutch, then shift transmission through all forward gears while checking ignition timing in each gear. The system is functioning correctly if timing advances 5 degrees or more when transmission is shifted into 4th or 5th gear. If not, go to next step.
- Check vacuum switching valve by disconnecting Green wire connector. Start engine, maintain speed at 2500-2800 RPM, and check timing. Connect Green wire connector directly to battery positive terminal.
- Timing should advance 5 degrees or more. If not, replace top gear detecting switch. If timing does not change through entire test procedure, replace vacuum switching valve.
- Check electrical system at function test connector. See Fig 1. Turn ignition on (DO NOT start engine). Check voltage across terminals "A" and "B". Reading should be zero (0) volts in 4th gear, 12 volts in all other gear positions. If not, check harness and/or fuse.
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