Mazda 323/626/929/GLC/MX-6/RX-7 1978-1989




The air gap (between the signal rotor and pickup coil when one of the rotor spokes is lined up with the pickup coil) can be measured with a feeler gauge.

1979-82 Except RX-7

See Figures 1, 2 and 3

  1. Remove the distributor cap and rotor. Turn the engine over (using the starter or by using a socket wrench on the crankshaft pulley bolt) until one of the four high points on the pole piece lines up directly with the metallic portion of the pickup coil.
  3. Using a non-magnetic (i.e. brass or paper) feeler gauge, check the gap. If it is not 0.010-0.018 in. (0.25-0.45mm) for the GLC, or more than 0.008 in. (0.2mm) wide for the 626, loosen the two adjusting screws and slide the pickup in or out until the dimension is correct. Tighten the screws and recheck the gap. Readjust if necessary.

1980-85 RX-7

Air gap is checked in the same manner as for the other Mazda engines described earlier, but is not adjustable. If the air gap is not within 0.020-0.035 in. (0.5-0.9mm), the only way to correct it is to replace the entire pickup coil base/bearing assembly or the distributor driveshaft. Checking the air gap should not be considered a routine tune-up procedure.

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Fig. Fig. 1: Unfasten the retaining screws and remove the distributor cap

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Fig. Fig. 2: Unfasten and remove the rotor

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Fig. Fig. 3: Measuring the air gap on 1979-82 electronic ignition systems