Air flow is absolutely necessary for your engine, that is unless it’s leaking in through the intake manifold.

Bolting on an aftermarket intake manifold has long been the introduction to hands-on hot rodding. Improved looks, performance, and, often, fuel economy can be just an intake swap away. Not to ...

A manifold leak will throw the engine’s fuel-air ratio out the window and can cause poor cold running and hard starting. The old school way of checking for a vacuum leak is to get the engine idling ...

A vacuum leak anywhere in the engine’s intake manifold system will cause rough running, stalling and be most problematic as the engine returns to idle.