The dealership can deny a free job repair if they have proof that your mod caused the damage. If this is the case, you should not expect them to repair your car for free.
The dealership will still have to honor the warranty for all unrelated repairs.
The aftermarket downpipe is higher flow...
All downpipes will trigger a check engine light unless they use GESI or HJS cats.
The most popular brands are Active Autowerke (GESI) and Fabspeed (HJS)
Clarification on this issue as it comes up a lot. BMW treats all aftermarket companies the same, Dinan does not get any special treatment. If a dealership decides not to do a specific job for free, it won't matter whether you have Dinan or JB4.
Dinan matches BMW's warranty and will cover the...