Ignition Basic Adjustment (12 Nz, C 12 Nz, C 14 Nz)
Precondition: Engine at operating temperature (oil temperature ≥ 80 ° C/176 ° F). Ignition off.
Connect Diagnostic Switch KM-640 to diagnostic plug in fuse box (see illus. I) and set to position "B".
Start engine and read off ignition point using stroboscope or Opel/Vauxhall tester. Ignition point must be 10 ° BTDC at 700-1000 rpm. Checking with stroboscope: Marks on pulley and on lower toothed belt cover must align (see illus. II).
If 10 ° BTDC is not read off or the marks do not align, correct the basic ignition point by turning the distributor.
Switch off ignition and disconnect Diagnostic Switch KM-640 from diagnostic plug.