Applications: 2003-’05 Rio 1.6
Customer Concern: The check engine light is on and there is a mass air flow (MAF) sensor range/performance code in the system. The engine will hesitate at times.
Tech Tips: The P0101 code is more of a rationality check. The MAF sensor signal isn’t rationally making sense comparing to things like throttle position and engine rpm.
Tests/Procedures:
1. Check freeze-frame data for engine parameters when the code sets, and get the throttle position sensor (TPS) voltage, MAF sensor voltage and engine rpm, etc. to help find a potential cause for the problem. Verify the re-flash for code P0101 has been performed; read Kia TSB under engine volume 3, #20 for a re-flash for this code.
2. Verify that there are no air leaks even a loose oil fill cap or a pulled out dipstick can set this code.
3. Check the MAF sensor for battery voltage on the red/green wire, ground on the yellow wire and output voltage on the green/yellow wire. Look for about 0.6 to 0.8 volts at warm idle.
4. Check the TPS signal voltage on the white wire specification is 0.2 to 0.8 volts closed throttle and then a nice, smooth voltage increase as the throttle is opened.
Courtesy of Identifix.