What is it?

What is it supposed to do?

And should it cost $250.00?

Also if its bad can it cause a gas smell from under the hood.

Any advice is appreciated.

 

It is the sensor that measures how much air is going into the engine, so that it can deliver the proper amount of fuel into the engine.

It helps maintain the stoichiometric ratio of air and fuel (12:1 approximately)

Yes, it can cost $250, but you can get a used or re-manufactured one for less.


Gas smell from under the hood is more likely caused by a leak somewhere in the fuel system (leaking injector, hole in a fuel line). Probably not the MAF's fault.