The check engine light is on and the vehicle blows smoke, particularly on the highway.

The vehicle consistently produced a small amount of black smoke while driving at highway speeds. Fault codes P0097 (IAT sensor 2 circuit low), P0649 (cruise control lamp circuit), and P0571 (brake switch circuit) were present. The P0649 and P0571 codes appeared instantly but did not illuminate the MIL and were attributed to aftermarket cruise control. The critical issue was the P0097, which reappeared after several kilometres of highway driving.