There’s a story floating around that your neighbor down the street installed a cold air intake, and that it immediately destroyed the car’s mass air flow sensor. But will a cold air intake really cause damage? The short answer is “no”, and, of course, there’s more to this story than meets the eye. That being said, we’ll describe how your mass air flow sensor, or “MAF”, works and why a cold air intake won’t do a thing to it.
How Mass Air Flow Sensors Work
As your engine sucks in fresh air, it needs to flow through the MAF’s bore and over a heated sensing wire or resistor. And, as we all know, when you blow on something, it gets cooler. The same holds true for the sensing element, so when a ton of air is being drawn in by your ride’s furious pistons, the MAF’s element is being chilled. This changes how much voltage can flow through it, which your computer reads and uses to instruct fuel injectors to add more or less fuel accordingly.
MAFs Can Be Damaged by the Following
- Running an intake without a filter: The MAF can’t send an accurate signal through bugs and dirt, so put that filter back on. It’s not restricting flow as badly as you may think
- Spraying injector or brake cleaner directly onto the air filter or MAF sensing wire: There’s a specific mass air flow sensor cleaning spray, don’t confuse it with other cleaners
- Touching the MAF’s sensing element: The oils and acids on your skin will contaminate the sensor
- Never cleaning your intake’s filter: This will eventually make the filter element break down, causing, oiled gauze, bugs and whatever else that’s caught into it to crash into the MAF’s sensing element
- Not tightening the battery’s terminal connections after installing an intake: Every time the battery’s cables make adequate contact with the terminals, damaging voltage spikes can be created, potentially frying your mass air flow sensor
- Driving through puddles or torrential downpours with a low-slung cold air intake installed and not using a hydroshield on its filter
- Over-oiling an air filter while cleaning: You only need to discolor the filter with oil for it to work correctly, so if you’re going through a bottle of oil each time you clean your filter, you’re using way too much