2. We coated both hot wire and film style sensors with K&N filter oil in both controlled (laboratory) and uncontrolled (real world) environments - none triggered check engine lights. We created extreme conditions, beyond anything an engine would ever experience such as submersing a MAF sensor in filter oil and monitored the sensor readings while spraying it with test dust. Even under these circumstances, the MAF sensor was not damaged. In addition, we were able to take this same MAF sensor, clean it, and found that the readings were identical to the ones taken prior to the extreme testing.
3. A majority of the "failed" sensors we retrieved from dealerships had not failed at all. They tested to be functioning within normal operating parameters as calibrated against new sensors purchased through dealership parts and service departments.
4. Few, if any, automotive dealership service centers have the testing equipment to authenticate a mass airflow sensor failure.
5. Many of the sensors tested were self-contaminated by the silicone potting compound used in the manufacture of the MAF. Some manufacturers have issued TSB's (Technical Service Bulletins) advising dealerships of the occurrence of MAF's contaminating themselves with their own silicone potting compound.
6. Sensors fail and are even the subject of full recalls by vehicle manufacturers. For information on recalls visit: www.recalls.gov.
For a list of our MAF sensor testing results along with the dealerships involved go to our MAF Sensor Test Results page.
An In-Depth Look at How Mass Air Flow Sensors Work