Remapping, warranty and insurance: the straight version

What a warranty can actually do

A manufacturer cannot void an entire warranty because you remapped the car. What it can do is decline a specific claim it believes is related to the modification, and in practice that means anything on the engine, gearbox or driveline.

Your door handle will still be covered. Your turbo is a conversation, and you may lose it.

Can they tell?

Usually, yes. Modern ECUs log a flash counter and often a checksum, and a dealer can read both. Assuming otherwise is how people end up arguing from a weak position.

We will put your original file back before a warranty visit if you ask. The flash counter will still show the writes, so this is damage limitation rather than concealment, and we will say that plainly rather than sell it as a fix.

Anybody who tells you a remap is undetectable is either out of date or lying.

Insurance is not optional

This one is simple. A remap is a modification and you must declare it. Most insurers will cover a Stage 1, frequently for a very small increase and sometimes for nothing.

Not declaring it risks the policy being treated as invalid — not just for an engine claim, for anything. A non-fault accident becomes your problem entirely. The premium increase is trivial next to that exposure.

How to declare it without drama

Ring them, say the car has had an ECU remap, give the stage and the power figure. That is the whole conversation. If they want written confirmation of what was done, we will provide it.

Specialist insurers handle this routinely and are often cheaper than a mainstream insurer's modification loading.

And when you sell it

Declare it to the buyer. A remap is not a defect and plenty of buyers see it as a positive, but a buyer who finds out afterwards has a legitimate grievance.

If you would rather sell it standard, bring it in and we will put the original file back.