How we work

What you can check without taking our word for it

The process, step by step

1. Enquiry and price

   you message us with make, model, engine and year, and what you'd like done. We tell you whether your vehicle is a good candidate, how its ECU is worked on, where it's best to do it and the price. If we're not convinced, we tell you at this point, before you move the car.

2. Diagnostics

   we read fault codes from every control unit, not just the engine one, and check whatever affects the job: clutch, turbo, particulate filter, automatic gearbox. If something needs sorting, we stop and explain it to you.

3. ECU identification

   we note the make, model, hardware and software numbers. That tells us which reading method is safe for that unit.

4. Reading and copying the original

   through the diagnostic socket, on the bench or by opening the ECU, depending on the case. We keep the power supply stable throughout, because a power cut halfway through a read or write is the most common way to damage an ECU.

5. Checking the copy

   we verify that the file read is complete and matches the vehicle. If the ECU had already been modified by another workshop, we'll tell you before going any further.

6. Developing the file

   we modify your ECU's software in WinOLS, according to the job requested and the condition of the car. We don't load a generic file from another vehicle.

7. Writing

   we write the modified file with the checksum corrected, so the ECU accepts it as valid.

8. Running checks

   we clear fault codes, check they don't come back and test the vehicle while watching parameters such as boost pressure, temperatures and ECU corrections.

9. Handover

   we explain what's been changed, what you'll notice and what's worth keeping an eye on. The invoice describes the work done, and we also give you a document setting out the work carried out, which is useful, for example, for your insurer.

For jobs that aren't remapping (an ECU clone, a key, an activation) the order is essentially the same: identify, read, save a copy, do the work and check.

The copy of the original, our number one rule

Before writing a single line to an ECU, we read and copy its entire original contents. It's the least glamorous part of the job and the most important, because:

• It's what lets you go back to stock: to sell the car, to take it to the dealer or because you've changed your mind. We explain it on back to stock software.
• It's the starting point for the modified file: we work on the exact software of your ECU, not an approximation.
• It's the safety net if something doesn't go as it should: there's always known-good software to write back.

When the reading method allows it, we prefer the most complete read (on the bench or in boot mode) to the most convenient one, even if it takes us longer: a partial read via the diagnostic socket may be enough to modify, but not always as a backup.

The original file is a working tool for the workshop: we don't hand a copy to the customer.

WinOLS and the EVC licence

WinOLS is the industry-standard software for editing ECU software: it lets you locate the maps in the file (tables of values the ECU looks up to decide injection, boost, ignition or torque), modify them and compare versions. It's developed by EVC electronic, a German company that sells each licence tied to its holder.

Pirated copies of the program are in circulation. Why should that matter to you? Because a legitimate licence is linked to an identified person or company, receives updates and access to the official add-ons, and leaves a trail. EVC offers a public check: the link on our EVC WinOLS licence (verifiable at evc.de), also in the footer of every page, opens its website and shows the licence status. You can check it before you call us.

The tool doesn't do the job on its own: the result depends on knowing what to touch and, above all, what not to touch on each engine. But starting with a legal licence is the bare minimum.

At the workshop or wherever your vehicle is

We work at our workshop in Alcalá de Henares and we come to the customer's home, garage or business anywhere in the Community of Madrid. If your ECU can be read through the diagnostic socket, the job can be done next to your vehicle. If it has to be removed and opened, we'll recommend doing it at the workshop, with the unit on the bench and under controlled conditions. More detail on mobile service.

If something isn't as you expected

It can happen: a warning light that appears days later, behaviour you're not happy with, a fault that has nothing to do with the software but happens at the same time. What we do:

1. Message or call us telling us what you're noticing and since when.
2. We check it: we read fault codes and parameters to see whether it's related to the job.
3. If it's the file, we tell you what needs correcting and how.
4. If it's something else, we explain it with the data in front of us and tell you how to sort it.

Warranty

Our work carries the statutory warranty in force, in line with the regulations governing vehicle repair workshops (Real Decreto 1457/1986, Spain's regulation on vehicle repair workshops, whose article 16 sets three months or 2,000 km for passenger cars, whichever comes first, from handover). We don't offer any conditions beyond that statutory warranty.

What we don't do

• Write generic or downloaded files, or files of unknown origin that you bring us.
• Remap a vehicle with unresolved faults that the new software could make worse.
• Delete emissions control systems on vehicles driven on public roads. Only for motorsport or off-road use, as we explain on deletes.
• Touch the speed limiter or tachograph on vehicles required to have them, or the odometer.
• Promise you a figure for the gain before we know your vehicle. What each engine gains depends on the engine and its condition.

Reviewed on 15 October 2026.