Hello Car Talk Community!
First and foremost, thanks for providing your collective expert advice.
I drive a 2005 Kia Rio with 48,000 miles. Every once in awhile (particularly after a bit of driving when everything is warmed up) the RPM won’t go past 2,500. I’ll put it in 1st gear, accelerate till 2,500, but as soon as it gets there, the engine gets groggy, the car slows down, and I have to quickly switch to 2nd and repeat the cycle on every gear. Flooring it makes it worse. Obviously the fastest I can possibly go with this happening is about 50mph on 5th (just below 2,500). This has happened three times and it has fixed itself every time so far.
A possible clue may be that the check engine light frequently comes on, and its always the same culprit: this “flow meter” sensor. I’ve had it replaced three times now, but it still always trips the engine light. I now just ignore the check engine light.