Hey, guys. I’ve owned my 2012 Mazda3 Skyactiv for almost 13 years now, and I hope to keep it for at least another decade, if not longer. The car has low mileage at almost 84K with no visible signs of rust on the body.

I recently had my brake fluid replaced since I had to get new front brakes and I also had a coolant flush just yesterday. My mechanic had mentioned my coolant was fine, but I insisted it be replaced since the owner’s manual recommended replacement at 10 years. He’s a pretty no-frills kind of mechanic, which I appreciate because I save money in the short-term, but I do wonder if maybe he’s missing certain things. Other than the brakes and coolant flush, the car has only had oil changes.

I should also mention my check-engine light has been on for months. My mechanic told me it was an oxygen sensor error code, but they so rarely fail, so he didn’t recommend I spend money to replace them since it might not remove the error code. He couldn’t seem to find the source of the error at my appointment yesterday. He checked for leaks in my exhaust, loose wires, etc. but nothing stood out. So my check-engine light remains on… I have no idea if this is doing long-term damage, but he doesn’t seem concerned at all.

Is there anything else you would recommend I service at this point? Power steering fluid and transmission fluid flush? Engine decarbonization?

Thanks!