I have a 2012 Kia Sorento that has lost its strength/power when getting up to highway speeds (65 mpg highway speeds here in CA. it struggles to do it. It doesn’t stop wanting to move forward though) and while going up hills. Once it gets up to speed it doesn’t kick into the next gear like it should all the time. It will just rev high until I take my foot off the gas and then it will change gears. Also my average gas mileage was about 20 MPG but it’s gone down to about 12 mpg on average. There was this one day where the average started at 10 mpg and then shot up to 30 mpg (which I have never seen it do before ever), seemed to drive fine (I didn’t push it though) and gradually dropped back down to about 20 (my normal average). The next time I drove it it went back down to averaging about 12 mpg again. All this has progressed over about a months time.
I took it to a local garage where they charge $200 for a diagnostic. I had them do it and they called me back saying there were no codes when they checked and they had used all their diagnostic time and would have to charge me for another diagnostic (so another $200) to keep looking for the issue. They thought it was a blockage of some sort in the exhaust. They ran a camera up there I guess and didn’t see anything though. I declined the second diagnostic ($400 to just diagnose the issue without finding a fix seemed to be a bit much). I’m getting ready to take it to a dealership since it has a recall on it for possible metal shards in the engine. Also they want me to bring it in for a software update.
It almost seems like it’s in “Limp Home Mode” but no lights are on (no check engine light or anything on at all”.
Any thought or idea’s? I’m worried this will turn into a money pit. I would super appreciate any input or things to ask the garage to check for.