P0664: Intake Manifold Tuning Valve Control Circuit Low Bank 2

What does P0664 mean?

The intake manifold tuning valve switches the manifold length or plenum connection with engine speed (more torque low, more power high); it is not the runner or swirl flap (IMRC, P2004 ff). P0664 means the bank 2 control circuit voltage is too low with the driver off – typically a short to ground; with GM-style logic an open circuit is included. Bank 2 codes require a V-engine manifold with two separately switched valves; many V engines use a single central valve between the plenums, and no manufacturer document available to us uses this code, so the description follows bank 1. At GM the bank 1 equivalent (P0661) flags 0.5 Ω or less to ground in 40 of 50 samples, with the lamp after two trips.

The code tells you which monitor failed, not which part is broken. Test before replacing parts.

Symptoms

• Check engine light (depending on the maker)
• Loss of power in part of the rev range
• Actuator does not click when switching

Common causes

• High Bank 2 control wire shorted to ground
• Medium Bank 2 actuator shorted internally to ground
• Medium Open circuit (included with GM-style logic)
• Low Output driver in the engine module faulty

Likelihood is a general estimate across vehicles; your make and model may differ.