Test 7: Intake Restriction: Purpose
WARNING: This page is about a different car, the 2003 Ford Pickup, 2003 Ford F550 Super Duty, 2003 Ford F450 Super Duty, 2003 Ford Excursion, and 2003 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
This is a visual inspection to determine if an air intake restriction is contributing to a low power condition. If engine does have a high air intake restriction, a large amount of Black or Blue smoke will be produced.