Mercedes Tuning and ECU Remapping

Most people arrive at Mercedes tuning expecting a conversation about power. For the majority of
cars that come through our workshop it is the wrong conversation – and the right one gets you
a better car.

Most Mercedes we map are diesel

Of the Mercedes variants we hold data for, 560 are diesel and 492 petrol. That
matters, because a diesel responds to remapping quite differently to an AMG petrol V8. On a
C-Class, E-Class, Sprinter or GLC diesel the useful change is mid-range torque
– the engine stops working so hard at the speeds you actually drive at, which is felt as
easier progress and, driven the same way, usually less fuel. Peak power barely enters into it.

On the AMG petrol cars the picture flips, and headline power genuinely is the point.

The badge tells you less than the engine

A 63 badge has covered several completely different engines. The 6.2 naturally aspirated
V8 in the early E63 and C63 is a different proposition from the 5.5 biturbo
that replaced it, which is different again from the current 4.0 biturbo. The
forced-induction cars respond far more to software than the naturally aspirated ones do – and
anyone quoting you big numbers for a 6.2 from a remap alone is not being straight with you.

The same applies at the other end of the range: the 2.1 diesel was sold at a spread of different
outputs from the same basic engine. We work from your registration, not the badge.

Gearbox as well as engine

Plenty of Mercedes complaints are not engine complaints at all – they are the gearbox
holding gears too long, shifting lazily, or refusing to kick down when asked. The 7G-Tronic and
9G-Tronic transmissions have their own control unit and it can be recalibrated separately. On an
automatic Mercedes this is often the change owners actually notice most.

The ECUs we see

Across the Mercedes range the common units are Bosch MED17.7.2, MED17.7.3 and
MED17.7.1 on the petrol cars, Bosch ME9.7 on the older V8s, and
Bosch EDC16CP31, EDC17CP46 and EDC17CP57 plus Delphi CRD2, CRD3 and
CRD3E.1 on the diesels. Newer cars use Bosch MD1 and MG1, which are locked from the factory
– see Mercedes
MD1 and MG1 ECU unlocking for what that involves.

Which unit you have decides whether the file can be read through the OBD port or the ECU has to
come out and go on the bench. We confirm that before you commit to anything.

Mercedes models we have written up

• A45, CLA45 and GLA45 AMG (2018 on)
• A35, CLA35 and GLA35 AMG (2018 on)
• AMG GT, GT S and GT R
• E63 and E63 S AMG
• GLS 63 AMG – with our own dyno figures
• Sprinter – vans and fleets
• MD1 and MG1 ECU unlocking
• Mercedes servicing in Maidstone

Not listed does not mean not covered – those are simply the ones we have written up. We hold
data on over a thousand Mercedes variants.

How we do it

Every car is mapped and then verified on our own 2000bhp Mustang 4WD linked dyno at our workshop
in Maidstone, Kent, with 30 years’ trade experience and 2,200+ reviews behind us. Send us your
registration and we will tell you which engine and ECU you have, and what is realistic for it.