I have had the 109cdi for 2 months now, and found it underpowered when laden with my kit, i was unable to find either a 111 or 115with my spec and price range......so i contacted a renowned Merc & BMW tuner i have used before E Maps who travel to you, i have used Simon before and is reputation and maps are second to none
I initially asked for for 60 Nm torque map giving me 310 NM, i test drove the van, and although i could feel the difference i wanted a bit more, so he loaded a 80NM+ map making 330NM in all (115cdi torque) the difference was very apparent instantly
it is much more drivable, pulls in all gears, hills are no longer an issue either.
When i fitted the roof bars and pipe tube, this dropped top end speed by 5 -10 mph, this is now back with more to spare
it runs smoother all round , seems quieter, revs over much easier and does not smoke result!!! Too early to tell if MPG has increased, but going on other results with real world use it should with more low end torque by 1-2 MPG.
All this is done without lifting the bonnet, first a fault code reader is plugged into the ODB port (located under the steering wheel to the right of the accelerator) to check for any problems, i had none, then your own map is sucked out and modified then re loaded into the ECU, no old fashioned soldering or smokey tuning boxes.
It now runs ~125bhp and 330NM oh and driving is now much more fun and enjoyable
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