Car tuning

[Paul C95]

Is it possible for a car tuner to tell if a car has been tuned by previous owner and if so what company tuned the car?

[Cupramax]

In order, yes and unlikely.

[Slushbox]

There's several methods of 'tuning':

An add-on box which intercepts CR and air sensors and fools the ECU into producing more rail pressure and more boost. They can be removed in minutes. Whether they leave any traces (elevated boost/fuelling logs?) is debated in the VAG forums. My MkV Golf Tdi had one, replaced by a Revo tune.

Replacement maps from Revo etc: Revo said they were not detectable but again, opinions say that on recent VAG cars third party ECU flashes are now detected and flagged up. Main dealer didn't pick up my Revo tune in 2008, but made me sign a disclaimer when I asked them not to update the ECU software.

Don't know if it's possible to detect whose tune is in the ECU. Revo came with a programmer you plugged into the OBD socket, which could revert to ECU to stock for servicing, then re-upload the boosted tune. So it recognised 'something', it couldn't upload the boosty tune to another car. Revo dealer could also recognise the ECU/car/something and re-update the tune if VAG servicing over-wrote it.

Edited by Slushbox on Monday 11th March 10:40

[Jefferson Steelflex]

That's interesting...my TTS has a remap - when it comes to service time (June/July I think) do I need to ask the dealer about ECU updates?

On topic, I was told my remap wasn't detectable unless they were specifically looking for it.

[xjay1337]

You won't be able to tell who tuned it yourself but if you look at the map in a suitable reader sometimes the tuner has labelled themselves in the hex somewhere.