Attention: On engines with Motronic, the ignition timing can only be checked, not set. In case of deviations from the specified values, it is necessary to determine the failed elements of the ignition system and replace them.
Warm up the engine. The operating temperature is reached from the moment the lower radiator water hose warms up.
Four cylinder engine
Start the engine, leave it to idle and measure the closing angle.
Attention: The closing angle is determined by the design and can only be checked, not adjusted. If the measurement result does not correspond to the specified value, check the pulse sensor in the ignition distributor (work must be done at a service station).
Depending on the model, disconnect 1 or 2 vacuum hoses from the vacuum diaphragm -1- of the ignition distributor.
Attention. On vehicles with automatic transmission, there is only one vacuum hose with a double diaphragm. 8 In this case, the 2nd fitting remains open.
Raise the engine speed to the reference value (see ignition timing table).
Aim the stroboscope at the arrow on the timing case cover.
Caution: Be careful with rotating pulley and belt.
With a normally set ignition timing, the marks -F- and -E- must be stationary relative to each other (see ignition timing table).
If both marks do not match, loosen the coupling bolt -2- on the ignition distributor and turn the distributor until the marks match. To remove the ignition distributor, lightly tap the vacuum diaphragm with the handle of a screwdriver in the direction of rotation. On 320i and 325i models, turn the ignition distributor by the teeth.
Tighten the mounting bolt.
Check idle speed adjustment.
In conclusion, check the ignition timing again.
Disconnect gauges, connect vacuum hoses. With a double diaphragm, the black hose is connected to a thinner fitting (for setting an earlier ignition), and a white or white-black hose to a thicker fitting (to install a later ignition).