System Check
- Disconnect hose from TC. Raise and support the front of the vehicle. Put the transmission in second gear and check for vacuum with vehicle speed above 10 MPH and engine speed above 800 RPM. There should be vacuum. If there is vacuum, go to step 10).
- If there is no vacuum, check for voltage at the TC solenoid valve with vehicle speed above 10 MPH and engine speed above 800 RPM. If voltage is not present, go to step 4). If voltage is present, disconnect the vacuum hose from the TC solenoid valve and check for vacuum.
- If there is vacuum, replace the TC solenoid and retest. If there is no vacuum, check the vacuum line to the TC solenoid valve for leaks or blockage, and the carburetor port for blockage. Clean and repair as necessary.
- Disconnect hose number 4 from vacuum switch B and apply vacuum. Ensure voltage is available at Black/Red wire below 2 in. Hg. If not, replace vacuum switch B.
- Turn ignition on. Check for voltage at Blue wire between control unit and ignition coil. If there is no voltage, check the wiring between control unit and ignition coil.
- Check for voltage between Brown wire terminal of emission control box number 1 and body ground. Start engine and check for voltage during deceleration. If voltage is present, system is okay.
- If no voltage is present, disconnect vacuum hose number 1 from emission control box number 1. Check for vacuum. If no vacuum is present, check vacuum hose for leaks, blockage, or disconnected hose. Repair any problems and retest.
- If vacuum is present, check vacuum hose for leaks in emission control box number 1. If okay, replace the vacuum switch and retest.
- Check for voltage at Yellow/Green wire terminal of control unit connector and body ground with ignition on. If no voltage is present, check wiring and fuse. Ensure Black wire between control unit and ground has continuity.
- Connect hand vacuum pump to TC. Apply 20 in. Hg of vacuum with engine idling. If engine stops, system is okay. If engine does not stop, ensure TC linkage moves smoothly and throttle cable is properly adjusted. If okay, replace the TC and retest.