[kdog26372]

Originally Posted by bryan_f22

the above post is correct, but...

If BMW is cracking your ecu open to look for a flash tune, they are checking everything, and if that is the case, they will also see the data from a piggyback.

Remember, both are pushing your car past stock boost pressure, more tq, more hp, more fuel, air, etc...

The piggyback is tricking the ECU to run more boost, the ECU shows stock boost while in reality it is pushing more. So, no they will not see data from piggyback as that's not how it works. Now, if the piggyback throws off codes then they will see this, but in terms of piggyback data, it will simply be the same data in stock form. ECU won't show that you're running 14-15 psi of boost when you should be closer to 10.

A flash tune would I think be pretty easy to detect as the ECU itself was impacted and they could trace the instances of when data was altered I would think. However, I did have a Cobb flash tune on my 135i which I returned to stock for warranty issues. The dealer opened up a case after the dealer themselves installed an LSD for me after they botched the install and it was leaking and had to be replaced. They said I must of had a tune that blew the differential, so they opened a case, found nothing, and fixed the LSD without cost...Patrick BMW in Schaumburg, don't buy from them or have them do aftermarket work as they don't know what they are doing and they were one of the recommended installers for the LSD and then tried to deny this post-fact even though it was right on the website and they were happy to charge me $$$ for the install and openly said yes we're a preferred installer originally.

[crbalch]

Originally Posted by wakeofdeath

Again it depends, I know 2 tuners off the top of my head for N55 Stage1 who are under $1,000

And they are?