The first weeks after a remap: how to drive and what to monitor

A question we often hear when we hand a car back: "Do I need to take it easy for a few days?" The engine doesn't need running in like a new or rebuilt one. But the first weeks are the best chance to confirm that everything works as it should, in all the conditions a dyno cannot reproduce.

What changes in the first days

ECU adaptations. Many ECUs learn continuously: fuel and ignition corrections, throttle behaviour. After new software is written they largely start again from scratch. Small differences at idle or part throttle on the first drives are normal.

Gearbox adaptations. Automatics and DSG boxes relearn the clutch engagement points. Until they do, shifts may feel slightly different.

You. More mid-range torque means you reach speeds you didn't expect sooner. Give yourself time to get used to it, especially on wet roads.

How to drive: step by step

1. Gentle first drives. Drive as you always do. Let the ECU and gearbox adapt in normal conditions.
2. Always warm up. Wait for the oil to warm up, not just the coolant, before asking for full performance.
3. Build up gradually. Once a few days have passed with no odd signs, use the performance, always legally and safely.
4. Cool down at the end. After demanding driving, take the last few kilometres gently or idle briefly before switching off, so the turbo can cool.
5. The right fuel. The one the calibration was written for. Lower octane on petrol means more ignition corrections and less performance.

What is worth monitoring

You don't need race equipment. Your eyes are enough, plus, if you like, an OBD reader with a phone app.

• Boost. Actual should follow requested. If it stays consistently lower or spikes sharply, it needs checking.
• Ignition corrections (petrol). A few, occasionally, are normal, especially in hot weather. Constant corrections on every acceleration are not.
• Temperatures. Coolant and oil should stay where they were before. Exhaust gas temperature (EGT) is only visible if the car has a sensor; don't worry if your app doesn't show it.
• Smoke (diesel). A properly calibrated car does not produce a black cloud under normal acceleration.
• Oil. Check the level a little more often in the first weeks. A change in consumption is information.
• DPF regenerations. If they happen clearly more often than before, tell us.
• Clutch. If, in a high gear at low revs with a lot of throttle, the revs rise without the speed rising, the clutch is slipping.

How to keep a useful log

1. Connect the OBD reader and open the app before you set off.
2. Choose a few values: rpm, requested and actual boost, coolant and intake air temperature, ignition corrections on petrol.
3. Note the outside temperature, the fuel, and exactly what you felt and when.
4. Send us the file with your description. You don't need to interpret it yourself.

Use the phone only with the car stopped or let a passenger handle it. Safety comes first.

When to call us straight away

• A flashing engine warning light: usually means misfires. Ease off and get in touch.
• Limp mode (the car cuts power).
• Unusual noises, smoke, a burning smell.
• Clutch slip or jerky gear changes.

We keep a copy of the original software, and every change we make is checked again on the dyno.

Have a question about your own car? Start with the car finder or book a slot.