Codes P2006, P2004 and P2009, IMRC solenoid with IMRC valve?

HUDUMASAUD

MEMBER
2007 MAZDA 3
2.3L
4 CYL
2WD
AUTOMATIC
112,000 MILES

P2006 keeps popping up despite changing to a new one and it looks like the butterfly's solenoid is the reason for that because it is always running (sucking Air) whenever the engine is started.

How can I diagnose and fix it? Both solenoids show 32.7 ohms.

1 Reply

AL514

MECHANIC
4,795 POSTS

Hello, so the solenoid control for the Intake manifold runner control is constantly pulling a vacuum from the intake, does it stop if you unplug the solenoids electrical connector?
And you mention both solenoids are reading 32 Ohms, is that the old one and a new one you're measuring?
This is a Ground side-controlled solenoid, so if the wire running to the PCM is shorted to ground it will keep the solenoid on. Or if the driver in the PCM has burned out and shorted to ground internally, it will cause the same effect.
I have also seen solenoids installed backwards with the manifold vacuum hose installed on the incorrect port on the solenoid, this vacuum pulling backwards on the solenoids caused it to stay open constantly and actually cause a circuit code stored in the PCM.
There is also a Technical Service bulletin about a check valve being faulty (Diagrams 2,3 below).
But if you pull the electrical connector off and the solenoid closes, that means the control wire is being grounded somewhere when it shouldn't be. If you're sure there is constant vacuum on the solenoid.

Another thing, if you're still getting this P2009, that means the PCM is reading low circuit voltage when it shouldn't be. When a 2 wire solenoid is turned off, the PCM will read 12volts coming through the solenoid until it grounds the solenoid and turns it on, at that point it will read 0volts on the control wire. So, a P2009 can be either the control wire is shorted to ground somewhere, or it has shorted inside the PCM. You can check this by turning the key Off, unplug the solenoid and check the control wire for continuity to ground. If there is a reading to ground, the disconnect the PCM connector that goes to the solenoid and recheck for a short to ground. If it's still there is a wiring problem, it it's no longer reading continuity to ground, then is grounding through the PCM.

https://www.2carpros.com/articles/how-to-use-a-voltmeter

https://www.2carpros.com/articles/replace-intake-manifold-gasket

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