two. one air/fuel ratio sensor or upstream sensor, and one oxygen sensor or downstream sensor. when replacing them make sure they are the cause and not the symptom of something else and also only use direct fit, universal are known to have to many problems and need to be wired in
The 2001 Kia Optima has 16 valves.
The 2001 Kia Optima's engine produces 149 hp @ 6000 rpm.
The gas tank on the 2001 Kia Optima holds 17.2 gal..
The 2001 Kia Optima has an inline 4 engine.
The 2001 Kia Optima is a gas-powered vehicle.
The 2001 Kia Optima has a 5-speed manual.
The height of the 2001 Kia Optima is 4 ft. 7.5 in. (55.5 in.).
The 2001 Kia Optima has double overhead cam (DOHC).
The 2001 Kia Optima is 15 ft. 5.9 in. (185.9 in.) long.
The 2001 Kia Optima runs on regular unleaded.
The 2001 Kia Optima has 36.2 in. of rear leg room.
The 2001 Kia Optima has 37.6 in. of rear head room.