Maintenance of the Motronic ignition system
The distributor cap of the Transporter T4 should be cleaned regularly inside and out to remove carbon deposits, dust and moisture.
It is also necessary to clean the ignition distributor rotor. For cleaning, use a cloth soaked in gasoline, at the same time visually check the distributor cap for cracks. The rotor (slider) of the ignition distributor must be replaced if its contacts are badly worn.
Brass contacts are not recommended to be ground or filed. The outer surface of all high-voltage wires must be kept dry and clean at all times in order to ensure flawless current transfer in the ignition system. From time to time, all wires must be removed from the ignition distributor, cleaned and checked at their tips. The wires must not be shortened to repair damaged ends: in such cases, the wires must be replaced.