Three problems related to engine have been reported for the 2004 BMW 330. The most recently reported issues are listed below.
This problem is occurring on all e46 330 m54 engines with the zhp(performance package) there have been numerous complaints to BMW na about this issue. At 2000 - 3000 rpms the engine rattles like a coffee can full of marbles. I took my vehicle to BMW but they stated that this is perfectly normal. BMW is not willing to do anything about this issue. The issue is the dual vanos unit they put into the m54 engine is using belrin bushings and they are failing. There is a company called dr. Vanos that fixes this issue by rebuilding the oem vanos with upgraded bushings. This unit cost $500, which I am not willing to spend as I have a 100,000 mile warranty from BMW.
The vehicle is a 330cic which a purchased in 2007, there is a problem with the electrical system & oxygen sensors.
In 2005 when driving my car, the car began pulling unevenly, jerking gently on acceleration up a highway bridge and the problem persisted to the dealer for service. The ignition coils were replaced under warranty.