‘12 Optima EX 2.4L with 129,250 miles. Feels like I’m losing power with the engine and it tightens up like I’m pressing the brakes. When I press the accelerator it’s better and goes back to the weird feeling once I release the accelerator. No knocking/vibrations. No engine lights or other lights are on. Starts fine and goes into D fine. No change in fuel mpg and no gas smell. Air filter clean. Hooked up OBDII from AutoZone and no error codes. Any leads on how to fix will be appreciated.