You can tell when a manifold tuning valve is bad when oil is leaking through it. You also can tell by inserting the dipstick into the valve and seeing if oil comes out through the dipstick.
Trouble code P0662 means: Intake manifold tuning valve control circuit high (bank 1)
P-1078: Powertrain - Manufacturer Controlled DTC - Manufacturer Controlled Area: Intake manifold tuning valve system malfunction - high RPM Diagnosis: Hose leak/blockage, wiring, intake manifold tuning valve, intake manifold tuning valve actuator, ECM Probably not repairable by the owner.
right rear of engine connected to exhaust manifold.
on the side of the intake manifold. opposite side of the throttle body
According to my code reader "P0660 intake manifold tuning valve control circuit open bank 1"
the PVC valve should be located on the valve cover by the intake manifold on top of your engine block
Its called an "Intake Manifold Tuning Valve". Its function is to join or separate the two sides of the intake manifold. It has a minor effect on engine performance. It can be difficult or impossible to remove.
The EGR valve on a 2.5L 2005 pacifica is located behind the engine on the right hand side. shouold be same on '04It is on the driver side rear of the engine.
The PCV valve is located in the back of the lower intake manifold. It should have a 3/8" hose going from the PCV valve to a vacuum source on the upper intake manifold.
If you are looking for a valve in the heater hoses that restricts coolant flow, it does not have one.
It is on the valve body, inside the transmission.