Several readers of my blog asked me – what to do, to keep the BMW petrol engine in perfect order for a max long time?
In this entry, I will summarize the recommendations. Some of them are more specific for N43/N53, but most of them fit each petrol engine.

a. Oil change. Change the oil regularly. If the car is mostly used in city traffic, the max recommended oil change interval is 10.000km. If the car drives on the highway, the oil change interval can be increased to 15.000 km. The oil change intervals (25 .. 30.000km), recommended for BMW Longlife oils, is not a good idea. Use only a high-quality oil. Remember – the oil forgery also is a viral business. Don’t try to save on the oil and filter.
b. Use only high-quality fuel. Piezo injectors of DI engines (N43/N53/N63/N54) are very sensitive to any fuel impurities. Don’t drive with an empty fuel tank. When the fuel tank is empty, the fuel system (and after – HFPF, injectors) can “ingest” rubbish, which lives in the bottom of the fuel tank.
c. Replacement of the spark plugs. Spark plugs of N43/N53 engines serve for around 25 .. 30.000km. Don’t try the fakes (they are trendy, serve till 10.000km) – only NGK spark plugs are suitable for these engines! Evaluate the technical condition of the ignition coils. They also should be replaced periodically (50 .. 100.000km). The good news: Bosch/NGK ignition coils are not expensive.
d. Drive for longer distances. This is a specific requirement of N43/N53 (also for N54/N63) series engines. When driving long distances, the injectors are measured (necessary for a correct fuel mixture), the water is discharged from the exhaust (it can damage the Lambda probes and the NOx sensor), the exhaust is warmed up – it will give a positive impact to the longevity of CO and NOx catalytic converters.
e. Drive with a higher speed. Periodical longer (at least 30 minutes) driving sessions with a speed of 110+km/h – a specific need ofN43/N53 series engines. Only driving with such speed, the desulfation of the NOx catalytic converter will be in progress. In turn, this is vitally necessary to keep the longevity of the catalytic converter itself and – to ensure a normal performance of the engine. If the NOx catalytic converter is contaminated, the engine will run on an emergency mode (and the owner will not get any warning regarding this).
f. Drive aggressively. Periodical aggressive driving is a vital necessity of these engines. When you drive aggressively, the oil pump develops the max pressure and a large flow – it cleans oil channels. A larger gas flow cleans the inlet manifold and the exhaust. In such driving mode, the CO catalytic converters are heated up – it also positively impacts their performance. When driving aggressively periodically, you will not have to worry regarding “overgrowth” of the inlet manifold and the EGR valve; the CO catalytic converters will also serve for a longer time.
g. Take care that the engine (N43/N53) uses a Stratified charge. Only in Stratified charge injection mode, specific injector parameter measurements are performed. These measurements are critically necessary to create a correct fuel mixture. Only in Stratified charge mode, the correct working conditions of the CO catalytic converters is ensured. If the engine do not use a Stratified charge, the CO catalytic converters are damaged soon, the NOx catalytic converter is permanently destroyed.
h. Pay attention to the vibration and misfires. The vibration most often can be felt as the diesel engine sensation in idle or at low RPM. Misfires, instead, is the shivering of the engine – short-term vibration. The reason for these symptoms can be a small thing – not-timely replaced spark plug, some ignition coil. But, if these defects are not solved immediately, the consequences can cost a lot!
i. If you see the Check Engine symbol in KOMBI or feel a strong vibration; shivering – perform the engine diagnostics immediately! Such symptoms can be a leaking injector – if the unburned fuel gets in the exhaust, it can make a lot of damage! During a concise time, the CO and NOx catalytic converters, also the sensors (Lambda probes, the NOx sensor) can (nad will be) be damaged.
j. Perform a regular (not less than – when the oil is replaced) express diagnostics of the engine. The express diagnostics – reading of the DME error messages and a “quick look” at the basic parameters. If there are error messages in the DME error message memory – definitely pay attention to them. No error message is recorded without any reason! These 5 .. 10 minutes with INPA or ISTA can save you a lot of money!