I have a 2008 Fit Sport, MT, 200K miles. When idling the rpm surges (650-820 RPM) and there is some hesitation when accelerating. Gas mileage has also dropped from 35 mpg to 31. I’ve cleaned the throttle body and replaced the MAP sensor, and did an Idle Learn procedure, all with no luck. I did a scan and got the following codes: P0108, P0223, P0123, P2A00, P1172, P0113. Can’t find any vacuum leaks. Any ideas? I’m leaning towards a replacement throttle body.

 

Have you ever changed spark plugs and/or ignition coils???

 

Solved. I replaced the upstream O2 sensor and problem solved, runs like new. I was able to loosen up the sensor after running the engine for 10 mins and the exhaust was hot.