730d turbo(?) noise and lack of power

[Rik Gruwez]

Hello all,

Sorry to make this mail in English, but I do not speak or write German. I have an E38 730d, model year 2001. Since a couple of weeks, the engine makes a funny noise between 2,500 and 3,500 rpm. It is hard to describe this noise. It is not really a whistling noise coming from the turbo, but rather more of blowing noise, as if you would be driving with one of the doors ajar. The car also lacks power and feels sluggish, ever since the noise started. On the speedometer I can hardly reach 200 km/h. Before the problems started, I could easily get to 220 km/h. Yesterday the BMW replaced -- under warranty -- the turbo because they assumed this was the culprit of the problem. However, the situation remained unchanged. I test drove it this morning and still the engine feels sluggish. Top speed this time was 195 km/h.

The dealership is at a loss and the BMW representative for Belgium also does not know what is wrong. The did a full readout of the error codes using their diagnostic computer, but could not find anything wrong.

Does anyone know what could be the cause of my problem? You can reply here on the forum in English or in German, or mail me directly at gruwez@libertysoftware.be.

Thanks,
Rik Gruwez
Brugge, Belgium