Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Circuit Description
Mass Air Flow (MAF) sensor measure amount of air entering engine at a given time to determine fuel delivery. MAF sensor produces a frequency signal of about 2000 Hz at idle to 8000 Hz at maximum engine load. DTC will set if MAP signal does not match expected value based on barometric pressure, throttle position and engine speed parameters.
DTC will set when the following conditions are present:
- Engine is running.
- No TP sensor DTCs are set.
- No MAP sensor DTCs are set.
- No EVAP DTCs are set.
- EGR DTC P0401 is not set.
- MAF DTCs P0102 or P0103 is not set.
- System voltage is greater than 11 volts but less than 16 volts.
- Canister purge duty cycle is less than 99.6 percent.
- Change in throttle position is less than 3.9 percent.
- EGR duty cycle is less than 89.9 percent.
- EGR pintle position is less than 89.9 percent.
- Engine vacuum is less than 90 kPa.
- Throttle position is less than 89.8 percent.
- Listed conditions are met for greater than 2 seconds.
- Change in MAF sensor is greater than a calculated value.
NO RELATED
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.