You will need an accurate ohmmeter, a jumper wire and a 3.4 watt test light.
Before proceeding with troubleshooting, make sure that all connections are tight
and all wiring is intact.
- Check for spark at the coil high tension lead by removing the lead from
the distributor cap and holding it about 1⁄4 in.
from the engine block or other good ground. Use a heavy rubber glove or non-conductive
clamp, such as a fuse puller or clothes pin, to hold the wire. Crank the engine
and check for spark. If a good spark is noted, check the cap and rotor; if
the spark is weak or nonexistent, replace the high tension lead, clean and
tighten the connections and retest. If a weak spark is still noted, proceed
to step 2.
- Check the coil primary resistance. Connect an ohmmeter across the coil primary
terminals and check resistance on the low scale. Resistance should be 0.81–0.98@
70°F (21°C). If not, replace the coil.
- Check the coil secondary resistance. Connect an ohmmeter across the distributor
side of the coil and the coil center tower. Read resistance on the high scale.
Resistance should be 6,800–9,200@ 70°F (21°C). If resistance
is much higher (30,000–40,000), replace the coil.
- Next, remove the distributor cap and rotor. Crank the engine until a spoke
on the rotor is aligned with the pick-up coil contact. Use a flat feeler gauge
to check the gap. Gap should be 0.20–0.60mm. If not, gently bend the
pick-up coil contact to correct the adjustment on 1979 models. On 1980 and
later models, the gap is not adjustable. On these models, gap is corrected
by parts replacement.
- Using an ohmmeter, check the pick-up coil resistance. Disconnect the 2-wire
(red and green) connector at the distributor. The ignition switch should be
in the OFF position. Insert the probes of the ohmmeter in
the pick-up coil side of the connector. Resistance should be 760–840for
1979 models, or 1,05010% for 1980 and later models. If not, replace the pick-up
coil.
- Finally, test the ignition module. On 1979 models, connect the test light
between the positive and negative terminal of the ignition coil. Connect a
jumper wire between the positive coil terminal and the red wire of the pick-up
coil, at the connector that you unplugged in the previous test. Be sure that
you are attaching the wire to the pick-up coil side of the connector. Turn
the ignition switch ON. The test light should light. Disconnect
the jumper wire from the connector. The light should go out. If not, replace
the module.
On 1980 and later models, the only way to test the module is to substitute
a known good module in its place.
