Today’s first job took us to Holmbush, St Austell, where we carried out a Stage 1 performance remap on this BMW 118d. These cars remain a popular choice in Cornwall thanks to their balance of economy, comfort and reliability, and they respond very well to a professional ECU calibration.
Professional OBD Remapping with Correct Voltage Control
BMW diesels of this era are usually a simple and reliable OBD job using our Alientech KESS 3, although later models (around 2020 onwards) require our Magic Motorsport FLEX due to increased ECU encryption.
One common issue with BMWs is low system voltage during programming, which is why we always connect our CTEK professional battery conditioner when working on ECUs. Stable voltage is absolutely critical when reading or writing ECU data and is one of the small but important details that separates a professional remap from a risky one.
Fortunately, this particular 118d had a brand new battery, giving us an excellent, stable voltage throughout the process.
👉 Learn more about our approach on the ECU Remapping page.
Realistic Gains, Honest Expectations
BMW 118d models use several engine variants depending on year and specification, so power gains can vary. From experience, we typically see final outputs between 150bhp and 200bhp, with around 175bhp being the most common result.
Older models tend to sit at the lower end of that range, and at Kernowsport we always set expectations honestly before starting any work. These are smaller-capacity diesel engines, but even modest gains make a noticeable difference to:
- Throttle response
- Mid-range torque
- Overtaking confidence
- Everyday drivability
The result is a car that feels more eager and refined without compromising reliability or fuel economy.
Mobile BMW Remapping Across Cornwall
Based in Hayle, Kernowsport provides mobile BMW ECU remapping across Cornwall, including St Austell, Truro, Camborne, Redruth, Penzance and beyond.
Whether you’re looking for:
- A Stage 1 performance remap
- Improved fuel economy
- Safer overtaking and better torque delivery
we tailor every calibration to the vehicle, engine variant and owner’s needs.
👉 See more real-world examples in Our Work
👉 Book your remap via Contact Kernowsport












