Recommendation: Use grease for spark plug adaptors (ZKF 01. -. reference No. 0 890 300 029),see accessories lists.. PLUG TOP COILS Recommendation - Due to operating time and. aging, the spark plug connector becomes brittle and thus. untight in the sealing area of the spark plug, which may. cause misfiring.1. Switch off the ignition. Wait for 15 min. before demounting the ignition coil.This prevents voltage. peaks that could destroy control devices.2. Remove the. defective coil. 3. Apply a thin film of BERU spark plug. connector grease ZKF 01(order no. 0 890 300 029) into the. inner part of theconnector. 4. Attach the spark plug. connector to the coil. 5. Mount the coil with the connector. on the spark plug(heed the tightening torque). 6. Check the. primary connector contacts for oxidation andclean it, if. required.