A while ago I had the honor to diagnose E46. Not a “regular” E46, but Alpina B3 S.

I will mention some nuances, that remained in my memory.

1. Alpina has used an M52 series engine as a base (it has only intake VANOS) but installed MS43 DME with double-VANOS management (for intake and outlet).

2. Logically – the management of exhaust VANOS is inactive. But my disappointment was huge when I found, that also the intake VANOS is not used! The intake camshaft is placed in an exact position, regardless of RPM and torque. Alpina – how so?

3. Here, the air consumption of this engine in idle:

Impressive! Fuel consumption (it is proportional to the air consumption): 1.3 times higher than for similar M52 series engine, at least 1.5 times higher than for the N53B30 series engine in Homogeneous mode and 2 times higher than for N53B30 series engine in Stratified charge mode! Such a huge difference! In addition, the time difference between the development of these engines – not more than few years!

4. Unfortunately, otherwise – nothing interesting. Not even taking into account the poor efficiency, increased power (which results in a significantly higher exhaust temperature), the thermal management of Lambda probes – in on/off level… Without illusions – the probes are getting wildly overheated.

I’ll be honest – I expected more from Alpina. The disconnected VANOS left a feeling of disappointment. Also the responsivity and reaction of the engine – quite sad, comparing to the N53B30O0.