My girlfriends escape had its check engine light come on recently - she was also due for an inspection so I brought it into the dealership today. They said her mass air flow sensor was reading at 160 hertz, when it should be at 155. He said this could cause the car to just turn off while driving and was a major problem, etc. He also said that the PCM had to be reprogrammed. I know next to nothing about cars, but from what I've been told there is no reason the PCM should need to be reprogrammed. Most of my information came from another more general forum I use so I was hoping I could get some help here from people who know Fords.

Is the 3% difference in hertz really that big of a difference? If its not, is there a possible fix other then completely replacing the mass air flow sensor? The quoted price was quite a bit more then she would like to pay right now to get her car fixed, so we are hoping there is another solution.

 

The 160 Hertz is a BARO reading which is inferred via the mass air flow sensor. This reading would be correct for sea level. When I worked in California we saw readings anywhere from 150-159 at sea level, so I doubt the 5Hz difference is a big deal. the BARO reading is dependent more on altitude than anything else. Here in Denver the readings are about 144Hz.

Can you tell us what code was found that turned the CEL on? I can be more help with a code than what you have included in your post. Is your girlfriend experiencing any problems, or just the CEL?

Being told a difference of 5Hz will turn the car off is just, well, I can't use that language here. Unless the tech saw something related to the MAF sensor to lead him down this road, I have no idea why they would tell you something like that........reprogramming is not such a big deal, Ford comes out with updates all the time.

If you can provide me a code, and the VIN, preferrably by email or PM, I will check it out for you as to updates and reprogramming.