VIDEO: Mass Air Flow Sensor Diagnostics
A mass air flow sensor measures air entering the engine. This video is sponsored by NGK Spark Plugs.
Runners And Ports: How Modern Engines Manage Air
Variable-length intake runners change the length of the intake passages depending on engine speed and load.
Factory Air Freshener
The system uses air quality sensors outside and inside the vehicle.
LTF And STF Fuel Trim Feedback Loops
How to understand rich, lean and somewhere in between.
VIDEO: Using Airflow To Sell Cabin Air Filters
Andrew Markel introduces an inexpensive tool that can assist in selling cabin air filter replacements. Sponsored by Auto Value and Bumper to Bumper.
Volumetric Efficiency Diagnostics
A few years ago, I obtained an OBDII scan tool/dynamometer simulation/calculation program that can graph volumetric efficiency (VE) over rpms. Using real world vehicles, and no useful instructions, I devised a test sequence that allows a technician to see things another way. What is Volumetric Efficiency? Let’s keep this simple to start. An engine is
Be Careful When Replacing That Diesel Air Filter
Modern passenger and light-duty diesels with ECMs have mass airflow sensors and precisely control fuel delivery. Key to the efficiency and lifespan of the diesel engine is the diesel air filter. A restricted air filter will not affect fuel economy but will drastically affect power output. We asked prominent filter manufacturers for some diesel air
How Ford’s New Grille Shutters Control Airflow
Some new Ford vehicles feature active grille shutters — a new system that optimizes aerodynamics by using vents to control airflow through the grille to the cooling system and engine compartment. If air is required to cool the engine, the vents are opened. If no airflow is needed, the vents are shut, contributing to significantly
