Hyundai Repair: 2002 hyundai V6 Santa Fe, hyundai santa fe, caliper piston

Question
my service engine lite recently came on inside my car i changed the oil, checked the gas cap and made sure the water bottle for radiator was filled. when i took it too have the oil changed the repair guy said he smelled a burnt smell could you tell what that may be also i was wondering how much should a timing belt(it is due to be done) and a callipher(i need the left rear fixed) would cost to get repaired on my 2002 hyundai santa fe v6 also how much should of rear brakes also cost for my car the repair man charged me $338.00 for rear brakes and when he replaced my rear brakes he did not tell me about the callipher a freind looked at the brake job that he did and he said i needed a callipher because the new brakes were fine on the right side but the left side was metal to metal after 5 months of the brakes being repaired.  thank you in advance for your information i would greatly appreciate it!!!  

Answer
Hi, Theresa.

The burning odor is most likely caused by the brake issue.  Don't be sold on this being caused by your caliper, however.  The fact that the brakes are worn very unevenly is evidence that the worn side is staying applied, but this isn't necessarily caused by the caliper.  This could be caused by the pads binding in the caliper due to poor construction (pad backing plate too large), rust of the backing plate, or too much dirt in the pad shims.  It could also be caused by hydraulic pressure being held due to the failure of any component in the line to that wheel: blocked of an internal caliper passage, collapsed brake hose, or faulty master cylinder, or faulty ABS unit if you have ABS.  Or it could be caused by binding of the caliper slides or caliper piston.  

The way to tell for sure is to have a reputable brake mechanic check the vehicle and locate the issue.  Unfortunately, these people are hard to find.  It seems that the mechanics at most brake chain shops are trained that any sort of uneven pad wear indicates caliper(s) replacement is necessary, when this is far from the case.  Of course, the brake shops like it this way because it helps them sell much more expensive repairs.

The check engine lamp could be on for any number of reasons, but it's almost certainly not related to your brake issue.  To even have an idea why the lamp is on, the engine control module will need to be interrogated for trouble codes.  Most retail chain parts stores will do this for free now.  If you can get the trouble code-- I'm interested in the Pxxxx (x's represent numerical digits) code, not what the parts store thinks it means-- I'll be happy to advise you as to what I think the best approach will be toward finding and resolving the issue.