Intake Manifold Control Runner


Intake Manifold Control Runner

Today’s market requires vehicles to be more and more powerful, while providing strict emissions limits. To answer this challenge, automotive engineers are continually looking for new ways to improve engine performance without sacrificing its emissions. One of them is an intake manifold runner control system. It provides the best of both worlds, helping for boosting engine performance and improving fuel efficiency at the same time.


By design, an intake manifold runner control system is a set of computer-controlled or vacuum operated butterfly valves located inside an air intake manifold. Depending on the engine load and speed, they shorten or lengthen individual runners of an air intake manifold to optimize air flow to the cylinders. Thus, longer and narrower runners help for boosting performance at low speeds, while wider and longer ones make the engine produce more power within a higher RPM range. The butterfly valves must open and close at the right moment to ensure smooth and efficient engine operation. That’s why, most of them are motorized valves operated by the engine control unit.

Since an intake manifold runner control system is designed to improve engine performance and fuel efficiency, its failure or any irregularities in its operation will affect engine power and fuel consumption. Here are the most common symptoms saying that your intake manifold runner control system is running wrong:

Your check engine light comes on

The engine control module keeps an eye on your engine operation. If any problem is detected, it will turn on the check engine light.

Reduced engine performance

Poor acceleration, rough idling and other engine related problems can appear due to a malfunctioning intake manifold runner control system. Its butterfly valves can get stuck in the closed or open position or somewhere between, causing engine performance problems.

Increased fuel consumption

If one of your butterfly valves gets stuck open, your engine control unit will try to keep the perfect air/fuel mixture by forcing more fuel into the engine. This will significantly increase your fuel consumption.

Intake manifold runner control system troubleshooting

An intake manifold runner control system is very complex, which is why everything from its diagnosis to repairing should be left to a professional. Its troubleshooting involves specific equipment, a sophisticated knowledge and lots of labor.