 After owning four Hyundai's I was shocked when I took my 2013 Santa Fe in for an oil change and to find out why it had reduced power.  Even though the vehicle was still under warranty the service department let me know that the repairs to the part causing the problem wouldn't be covered under warranty.  When I asked why, I was told because of a lack of maintenance.  I offered to provide all of the receipts for maintenance that complied with the manufacturers recommendations and was told that wasn't necessary, they wouldn't honor the warranty anyway.  What surprised me even more was the fact that the oil line that caused the problem was under recall and had been replaced during the service - but was told that was unrelated - interesting.  Needless to say I had the car towed from the dealership to get a second opinion and was told that based on the maintenance record the damage couldn't have been caused by a lack of maintenance.  After serving in the military for 35 years I've never been accused of lying about having maintenance performed.  As a military pilot and aircraft owner I can attest to the importance of completing scheduled maintenance.  As I stated before I was absolutely shocked when I was told that this wouldn't be covered under the warranty.  After being a loyal customer for two decades and owning four (my family has owned about a dozen Hyundai's) you can bet I'll take my business somewhere else.  I hope the $2,533.88 in repair costs you tried to save by refusing to honor the warranty was worth flushing my future business....