How to detect a re-map?

[andyceb]

Hey there 

I am thinking of buying a Mk5 (currently own a Mk1 GTI) 

I have test driven 2 cars now, it was a few weeks between driving them but I can't help but think one was faster than the other... now my worry is which one is normal?  I guess one might be slow as its running in limp mode or something?  Or the faster one might have a re-map?

Well anyway this got me to thinking, I intend to re-map my car when I buy it but potentially I might end up remapping a already remapped car!?  I know remapping is 'undetectable' but how can I tell if its been carried out?!

Thanks guys 

[MPS]

The slower car may have had a duff Diverter valve thereby giving a sizeable loss in power as the boost will just leak through the splits in the rubber diaphragm inside the DV, common fault, £50 replacement part, fairly straightforward to replace.

[bacillus]

Surest way to tell is to log the boost using vcds.

[MPS]

....or one could be remapped! Lol. If the car does have a knackered DV, you can usually tell by hearing it when you put your foot down and the revs get to around 3k rpm, you'll hear an air leak type noise, this is the air leaking through the split rubber diaphragm.

[andyceb]

Thanks for the replies 

Interesting reading, especially about monitoring the boost to work out what map is being run!  Is VCDS similar to VAGCOM?  (I come from a world of mechanical fuel injection  so this is all new to me)  I will do some more searching on here 

[bacillus]

vcds is Ross Tech's latest name for vag-com.   

[cata_adc]

or make a dyno test ;)

[gazon69]

if you buy one and it's already mapped , where ever you take it , if you decide to map it, they will tell you if there is already a map present.

[andyceb]

if you buy one and it's already mapped , where ever you take it , if you decide to map it, they will tell you if there is already a map present.

That's what I would hope although I suspect some would take your money anyway!  Especially if they could use the argument "how could we know it was already re-mapped, its undetectable"

[cata_adc]

No it isn't. If they want to extra charge then they will use that argument. After you buy it go to a dyno test. Then you will know if it's maped or not 

[PDT]

Any 'real tuner' would be able to read your current ECU software and open it in software such as Win-ols and see that it has been altered from stock, it takes around 15 mins to read and 5 mins to compare with a stock file, 1/2 hour of labour should cover it so about £20.