Fig. 5: Testing Oxygen Sensor Heating
Element Resistance
Knock Sensor
Knock sensor must be tested with System Tester (M.S. 1700).
Speed Sensor
Disconnect speed sensor electrical connector from the sensor.
Using an ohmmeter, measure resistance between connector terminals "A"
and "B" (marked on connector). If reading is not 125-275 ohms with
engine at normal operating temperature, replace speed sensor.
"Synch Pulse" (Stator)
1) Using an analog voltmeter, insert positive probe into Blue
wire at distributor connector. Insert negative probe into Gray wire
with tracer at distributor connector.
NOTE: Do not remove connector from distributor. Insert voltmeter
leads from rear of connector. Do not puncture wire.
2) With voltmeter set on "15-Volt A/C" scale, turn ignition
on. Voltmeter should indicate 5 volts. If voltage is indicated, go to
step 4). If no voltage is indicated, check voltmeter leads for good
connection and go to next step.
3) If there is still no voltage reading, turn ignition off
and remove ECU. Reconnect harness and turn ignition off and remove
ECU. Reconnect harness and turn ignition on. Check for voltage between
ECU pin "C-16" and good ground. If voltage still does not register,
test system with System Tester (M.S. 1700).
4) If 5 volts was detected, check for continuity at the
following points:
* Between Blue wire at distributor connector and terminal "C-16"
at ECU.
* Between Gray wire with tracer at distributor connector and
terminal "C-5" at ECU.
* Between Black wire at distributor connector and good ground.