What does "mass airflow" mean in fault/error codes?

[Krazkat]

Yay, I finally figured out how to post!! I spoke to a person who has an 02 pt just like mine & she said that some shop told her the reason her pt was getting rather poor mileage was that something needed to be cleaned out , or blown out, and it has to do with mass air and is behind a flap? I asked about the air filter and she said that wasn't it, it was something else. Does this make sense to anyone?

[cdynaco]

Welcome to fuel injection. LOL Its been a learning curve for me too on my Mustang.
The MAF sensor is on the intake tube between the throttle body and the airbox. You can get special cleaner at an auto parts store. Easy to clean. Sometimes it gets grime (or oil if you use too much on a K&N type filter) on it and gives false readings to the PCM. While you're at it clean the throttle body too (same cleaner).

[Krazkat]

Thanks, I'll check into that!

[slartyblarfast]

The PT does not use a mass airflow sensor. The PT uses a manifold absolute pressure sensor. Sounds like she is talking about the throttle body. Carbon builds up on the bore and blade. Most likely cause of poor fuel economy is usually a vacuum leak or a slow or biased 02 sensor.