2011 kia optima sx
I meant the speed. Thank you. Last time I tried to take it to the shop the check engine light turned off. Now it's been back on since monday.The OP hasn't been on here for 1 1/2 years, so first, have the ecu checked for any codes, any AutoZone will do it free.
Really don't know how the mpg enters the equation, maybe you mean the speedometer?