Upper Limit

ECM-150A MASS AIR FLOW (MAF) SENSOR
UPPER LIMIT

Checking connector



- Ignition off.
- Check Mass Air Flow (MAF) sensor and pressure sensor connectors for contact resistance and oxidation according to [1][2]Checking Wiring and Terminals. Intermittent Faults


Check the values for the Mass Air Flow (MAF) and pressure sensors



- Start engine and run to normal operating temperature.
- Switch off all large power consuming components, for example the air conditioning (A/C) compressor, defroster and seat heaters.
- Read the Mass Air Flow (MAF) and pressure sensors values.
- Check that the Mass Air Flow (MAF) and pressure sensor values are within their various ranges at different engine speeds (RPM)

Mass Air Flow (MAF) sensor, table values. Mass Air Flow (MAF) Sensor
Manifold Absolute Pressure (MAP) sensor, table values, Manifold Absolute Pressure (MAP) Sensor

Are these values OK?
Yes - Testing Complete.
No - Continue below.


Checking component
Check for air leakage in the intake system. In particular check the hose between Mass Air Flow (MAF) sensor and throttle body (TB) for leakage and damage according to Check For Air Leaks In the Intake System

Check that the hose between the manifold absolute pressure (MAP) sensor and manifold is airtight and is not trapped.

Remedy as necessary.

Other information:
- To localize the manifold absolute pressure (MAP) sensor, Locations
- For information about signals/resistance values, Pinout Values and Diagnostic Parameters
- To access/replace the mass air flow (MAF) sensor, Mass Air Flow (MAF) Sensor, Replacing


Fault-tracing information
If the fault is intermittent, do not verify fault-tracing if the fault does not recur.