what is a 2001 chevrolet impala air mass sensor look like and where is it located?

Answer 1

The mass air flow sensor is located in the air tube that comes from the air filter housing.
It looks like a black plastic cylinder with a connector out one side.

Answer 2

Also known as MAF, 'Mass Air Flow Sensor'. Most fuel injected cars have one, and it is a fine wire or mesh, that is heated to a temperature of say 195 degrees, Fahrenheit.

As air flows through it after the air cleaner filter, on the way to the INTAKE manifold of the engine, that air cools the wire, and the computer senses the energy it needs to keep the temperature constant.

From that, we can deduce the amount of airflow, and, add the correct amount of fuel through the fuel injectors, for the engine to perform adequately. We want an optimal mix of 1 part of fuel to about 14 to 18 parts of air. 14:1 ("Rich") to 18:1 ("Lean").

So, look for a hard part of the air tube between the intake on top of the engine, and the aircleaner filter box, that has a wire atttached!

And, don't hit, or shake it too hard, especially when it is hot, while the engine is running, it glows like a toaster wire, sorta dull red to orange. Never spray water there, as it can shatter the tungsten wire.

These sensors run from $50 in the junk yard, up to $200 new, and there is often a version or revision number on it, to match a computer revision level for every car or truck, so you'll need to preserve that info! Wrong or broken one will make the engine run incorrectly.

The older systems used a vane sensor to measure air mass flow. Before the computers could work at high speeds, it did a good job, was cheap and reliable.