What is the Intake Manifold Runner Control all about?

Your engine needs air in order to combust fuel, and varying amounts depending on the speed and driving condition. Older cars relied on nothing more than a basic air intake that pulled fresh air in through the filter and delivered it to the intake manifold. However, newer cars have the means of adjusting the flow of air through the intake in relation to driving conditions. These vehicles are equipped with intake manifold runner control modules, which are vacuum solenoids that operate a butterfly valve in the intake. During slower driving when the need for air is less, the butterfly stays closed. However, in aggressive driving situations, the butterfly opens and increases the amount of air sent to the intake. The computer compensates for this by adjusting the fuel mixture, and the result is an increase in performance.

Keep in mind:

• The intake manifold runner control is not inspected during normal maintenance.
• Both open and closed positions can cause damage to the engine.

How it's done:

• The engine trim cover is removed from the top of the engine
• The defective intake manifold runner control is removed
• The new intake manifold runner control is installed
• The engine trim covers are reinstalled
• The engine is scanned and tested for proper operation

Our recommendation:

If the butterfly fails to open or close (sticks in one position or the other), the engine can sustain damage through either lean or rich running conditions. We recommend having the condition diagnosed by one of our expert mechanics.

What common symptoms indicate you may need to replace the Intake Manifold Runner Control?

• Reduced engine performance output
• Increased fuel consumption
• Check Engine light is on

How important is this service?

Considering the fact that a malfunctioning intake manifold runner control could cause both lean and rich operation, it’s important to have the controller’s operation checked. This will require our expert mechanics to retrieve the diagnostic codes via the OBDII connector and test the controller for operation. We recommend having this service performed immediately.