2. Check distributor cap, distributor rotor, ignition lines and spark plugs (Warning: ignition off). Resistance of spark plug wire including connector: approximately 6 k Ohm
Resistance of distributor rotor: approx. 5 k Ohm
Spark at spark plug yes
Repair high tension side
3. Check ignition timing Timing good?
Adjust ignition timing
4. Check fuel system
Engine receiving sufficient fuel?
Repair fuel system
5. Check ballast resistors and ignition coil (Ignition off, wires disconnected at resistors and ignition coil)
Ballast resistor (0.4 Ohm): 0.35 to 0.45 Ohm Ballast resistor (0.6 Ohm): 0.55 to 0.65 Ohm
Ignition coil primary (between terminals 1 and 15: 1.0 to 1.35 Ohm Ignition coil secondary (between terminals 1 and 4): 5.5 to 8.0 k Ohm
Replace ballast resistors or ignition coil f
Voltage value good?
Check lines and connections of ignition lock, ballast resistor, ignition coil and ignition control unit for voltage drop, and repair.
7. Check voltage at ignition control unit terminal 4 against ground (ignition on). Voltage must equal battery voltage.
Voltage valve good?
Check line from ignition lock to ignition control unit for voltage drop, and if necessary repair.
8. Check voltage at ignition coil terminal 1 against ground (ignition on). Voltage max. 2.0 V
Voltage value good?
Replace ignition control unit
9. Check dwell angle. Dwell angle:
52" to 70° at 1500 - 50 rpm Dwell angle: 42 to 68 at 5000 - 50 rpm
Dwell angle good?
Engine must start and/or engine output must be good, otherwise there is a mechanical defect.
Continued at point 10.
If sensor system is good, replace ignition control unit.
10. Check starting voltage. Connect voltmeter at ballast resistor shown (0.4 Ohm). Operate starter. Voltmeter must show battery voltage.
Starting voltage good?
Look for open circuit between battery and ballast resistor or at starter solenoid f
11. Measure distributor sensor resistance including sensor line at disconnected ignition control unit plug between terminals 1 and 2 (ignition off).
Resistance: 890 to 1285 Ohm
Resistance value good?
12. Check distributor sensor coil (including sensor line) for ground short at disconnected ignition control unit plug between terminal 1 and vehicle ground terminal 2 and vehicle ground (ignition off)
Resistance: oo (maximum)?
Replace distributor t yes f
13. Check distributor sensor system for mechanical damage.
Visual inspection: Gap between rotor and stator?
Distributor sensor good?
Replace distributor continued at point 5
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