How do i know if my used car has a performance chip on the ECU with out disassembling the ecu?

Question

i have a 98 jetta vr6 glx i did a little experiment with fuel octanes, i tried 89 octane than i tried 97 octane and it seemed my car loved every drop of 97 oct....... more than the 89 is there any way to forsure know if i have a chip with out plugging it in or....such activity...? thanks.

Answer 1

get a code scanner that is capable of reading real time data from the on board computer and compare those numbers to the numbers from a know non chiped car of same type