I have a 2003 3.0d with a STEINBAUER P-Box it improves the power up to 212bhp and 468Nm of torque. I haven’t done the remapping for several reasons:

- The gearbox cant take more than 500Nm of torque.

- Each time you go to the dealer, BMW will reset the ECU.

- Lost of the manufacturer guarantee. BMW can see if there was a modification in the software.

As for the fuel consumption, you have to consider an increase of fuel consumption in case of a pretty fast driving.
If you maintain your manner of driving you can expect the same or in some cases even lower fuel consumption.

Cheers

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