Modding's effect on a tune up?..

[Ian]

I was just wondering if doing mods related to the ECU, like putting on a piggyback system (S-AFC, FTC, etc.), effect the ability of a Toyota dealership mechanic, or whoever, do a tune up or a diagnostic check on your car? I would imagine that the parameters for everything related to your air, timing and fuel readings would be different so how could they check whether your car is functioning according to Toyota's standards.

For example, if you retard your timing by a degree using a piggyback system, wouldn't this complicate the mechanic's efforts to properly install a new timing belt?

[Mandarinsolara]

i dont know how much ratardation you are going to be doing with any piggyback... but yes, they will look at you with a far away look in their eyes.

timing belt is like... a take off old, and put on new kind of process. any tuning that should be done after that is minimal and should be relatively simple through your piggyback.

[DatSRBoi]

Upping the stuff shouldnt cause much issues. When you tune a car your just tuning it to handle the new toys you add on correctly. When you take it to the dealership that a/f will still run in the right spot as if it was still stock. Even if you had upped your timing. They would know to it and work with it. Unless they are unqualified BS people like the shop I went to.. Dam bastards broke something on my car..