How are the runners on the intake manifold controlled?
NOTE: On some applications, most notably Ford and related makes, the intake manifold has two separate, but relatively small-diameter runners for each cylinder. On these applications, the runner control flaps close off one runner completely at low engine speeds to increase the airflow rate through the other runner.
What does P2008 mean on an intake manifold runner?
P2008 means that the intake manifold runner circuit has an open electrical connection bank 1. The ECU tries to control the the angle of the intake manifold runner flappers and when it cannot control this circuit sets a Check Engine Light. Along with the Check Engine Light, a failsafe mode is set until normal operation resumes.
Why do you need an intake runner control flap?
While intake runner control flaps were reasonably effective in improving the flow dynamics of air through intake manifolds, the advent of variable length intake manifolds has made it possible to control the flow rate of intake air over a wider range of engine operating conditions.
How to check intake manifold runner flapper valve?
Use the scan tool to monitor solenoid operation while the engine is running and watch for changes. Install a hand vacuum pump to check for intake manifold runner flapper valve operation. Use a multimeter to check for continuity in the wiring.
Why does the ECU need to control intake runner?
As a practical matter, the increased airflow produces increased torque at low engine speeds since combustion is improved, which in turn, makes it easier for the ECU to control both long and short-term fuel trims to reduce emissions.
How does the distance of the intake runner change?
In practice, the distance that the intake air is forced to travel around the device is roughly equivalent to the air flowing through a runner of the same length, so by altering the position of the “scroll” within the manifold, the distance the intake air has to travel can be varied through an almost infinite range.