So about 3 weeks ago the check engine light on my 2017 Hyundai Santa Fe Sport Ultimate came on. Noticed it was taking a lot longer to start, and was idling rough. Used my scanner it threw system too rich, and gave me best options. It told me MAP (Manifold Absolute Pressure) sensor. Easy enough, I ordered an OEM MAP sensor, and after it got to me it took a whopping 10 minutes, two 10mm bolts and a plug later it was changed. I cleared the codes, unhooked the negative post of the battery for 15 minutes, hooked everything back up, and went on a test drive. Everything was great, started great, idled great, everything was great....until the next day. I took my wife to work (30 minute drive from home) and the check engine light is back on, throwing same codes, back to rough long starts, and rough idles. Any suggestions?

 

It sounds like a vacuum leak is probably the main issue with your Santa Fe Sport. Even though you replaced the MAP sensor, a vacuum leak can mess up the air-fuel mixture, causing rough starts and idling. Check all the vacuum hoses and connections for cracks or loose spots, and use a smoke machine if you have one to spot any leaks more easily.
Aside from that, make sure the oxygen sensors are working right, as faulty ones can throw off the air-fuel mix. Fuel injectors could also be an issue if they’re clogged or leaking. The MAF sensor might need cleaning if it’s dirty, and the fuel pressure regulator should be checked to ensure it's not causing too much fuel pressure.
If you’ve tried all these and still have problems, a professional diagnostic might be your next best bet. But starting with the vacuum leaks could be your best bet to get things running smoothly again.