Civic (1300 Calif. Man. Trans., 1300 & 1500 Calif. Auto. Trans.)

1. With engine cold, connect a vacuum gauge to vacuum advance hose on 1300 models and to vacuum hose 2 on 1500 models, then start engine.
2. If there is vacuum at idle on 1300 models, go on to step  5). If there is no vacuum at idle, check all hoses for obstructions or loose connections a hose fittings. If there is still no vacuum go on to step  4).
   Fig 1: Civic 1300 Ignition Timing Controls (Calif. Man. Trans. Only)

   Courtesy of AMERICAN HONDA MOTOR CO., INC.
3. If there is no vacuum at 3000 RPM on 1500 models, check hose and connections between distributor and carburetor port. Clean or replace. If there is vacuum at 3000 RPM, connect a vacuum gauge to hose 5  . If vacuum, is present at hose 5 replace purge control/unloader solenoid valve and retest. If there is no vacuum, go on to step  3).
4. With ignition on, check for voltage at ignition solenoid valve. If there is voltage, check for vacuum at inlet of ignition solenoid valve at an idle. If there is vacuum, replace ignition solenoid valve and retest. If there is vacuum, check for blockage in port in carburetor insulator block.
5. With engine warm and vacuum gauge connected to vacuum advance hose on 1300 models or connected to hose 2 on 1500 model, check for vacuum. If there is no vacuum on 1300 models, go on to step  7). If there is no vacuum on 1500 models, go on to step  9).
6. If vacuum remains, check thermosensor for continuity. If there is no continuity, replace ignition solenoid valve and retest. If there is continuity, replace thermosensor and retest.
7. Jack up front of car and support with safety stands. Push positive probe of voltmeter into Blue/White wire terminal at control box connector and connect negative probe to a ground. Start engine and accelerate slowly in second gear. If there is voltage go on to step  9). If there is no voltage, check electrical connections and check speed sensor.
8. With engine warm and vacuum gauge connected to vacuum hose 5 at distributor, check for vacuum. If there is vacuum, go on to step 9  ). If there is no vacuum, check purge control/unloader solenoid for voltage. If there is no voltage, replace purge control/unloader solenoid valve and retest. If there is voltage, replace thermosensor and retest.
9. Attach vacuum pump to vacuum advance diaphragm on 1300 models and to vacuum retard diaphragm fitting 5 on 1500 models. Start engine and draw 6 in. Hg vacuum. If timing advances or retards, test is complete. If vacuum does not change, replace diaphragm and retest.

Fig 2: Civic 1300 Ignition Timing Controls (Calif. Auto. Trans. Only)

Courtesy of AMERICAN HONDA MOTOR CO., INC.