2. On the M43TU 4-cylinder engine, check the condition of the high voltage wires as follows.
Note. On N42 engines, it is not possible to check the high voltage wires.
- A) Make sure the wires are labeled according to the cylinder numbers. Pull the tip of the first wire from the spark plug.
- b) Inspect the inside of the wire lug for corrosion, which appears as a white fluffy powder.
- V) Put the tip back on the candle. Check if it is tight on the candle. If not, then pull the tip off the spark plug again and squeeze the metal contact inside the tip with pliers.
- G) Wipe the wire along the entire length with a clean rag to remove dirt and traces of grease. Inspect the wire for cracks, blisters, or other damage. Do not bend the wire too sharply and do not try to stretch it - the conductor inside the wire may break.
- d) Reattach the wire to the spark plug.
- e) In the same way, check the remaining high-voltage wires.
3. Check up, whether the accelerator cable is correctly adjusted, as it is specified in chapter 4A.
4. If the engine is running very erratically. check the compression as indicated in chapter 2.
5. If these checks do not reveal the cause of the problem, contact a workshop or dealer for an instrumental check. If the malfunction really exists, then the BEU self-diagnosis system detected this malfunction and entered its code into its memory. The fault code can be retrieved from the memory of the BEU using a special device - a code reader that is connected to the diagnostic connector of your car. The code reader allows you to find the fault location quickly and easily, without resorting to the tedious procedure of sequentially checking systems and wires (which is dangerous for BEU).