What the P2070 code means
When trouble code P2070 sets, the engine control unit (ECU) has
determined that the intake manifold tuning (IMT) valve is stuck
open. The ECU gets this information from a position sensor that is
built into the tuning valve actuator. The IMT valve helps increase
engine torque by changing the length of the runner in the intake
manifold to match the conditions in which the vehicle is being
driven. When the tuning valve gets stuck open, it is possible that
the engine may not perform optimally.
What causes the P2070 code?
Trouble code P2070 sets when the engine management computer
detects that the intake manifold tuning valve has not moved from
the open position when commanded to close.
What are the symptoms of the P2070 code?
It is possible that you may feel a slight loss of power either in the
lower or upper RPM (revolutions per minute) depending on the
manufacturer of your vehicle.
The other symptom is that the Check Engine Light will come on.
How does a mechanic diagnose the P2070 code?
As always, I start diagnostics with a visual check of the system
involved with trouble code. Many times the problem can be
identified visually. Sometimes it could be as simple as some rodent
damage such as a chewed-through wire.
I know that some makes of vehicles use small plastic bushings to
hold actuator rods for the tuning valve. Oftentimes when this code
sets, you will find the plastic bushing nowhere to be found and the
actuator rod is hanging loose and not controlling the tuning valve.
If the actuator rods are still attached, it may be necessary to
disconnect the actuator rod and make sure that the valve moves
freely and is not binding or stuck. It may be possible for carbon or
oil sludge to build up in the intake manifold and cause the valve to
become stuck, or bind.
Once the integrity of the actuator rod and the valve itself are
confirmed, it may be time to look at the actuator that controls the
valve. Some are vacuum operated, and some may be controlled
with electric motors. With the vacuum actuated systems, it will be
necessary to confirm that there is vacuum being supplied to the
actuator, and then that the vacuum is being controlled by the
actuator. For the electronically controlled system you will need a
scan tool to be able to see if the position sensor is working
correctly.
Common mistakes when diagnosing the P2070 code
The most common mistake would be replacing the IMT valve
actuator without performing any visual inspections or diagnostics.
Another common mistake would be forgetting to check that the
valve is not binding or stuck in the manifold itself. If this is the case,
it could be an unexpected, very expensive engine repair for the
customer.
How serious is the P2070 code?
This code is not too serious. It is possible that you may notice
some slight power loss from the engine. Also, depending on your
state, this code may fail you for emissions inspection.
What repairs can fix the P2070 code?
The most common repair for this code in my experience is
replacing a missing or broken actuator rod bushing. When the
bushing is not in place, oftentimes the actuator rod will fall out of
the lever of the intake tuning valve.
Next would be replacing a faulty actuator valve for the intake
tuning valve.
After that would be some type of repair requiring the intake
manifold to be removed and cleaned, or to remove some type of
obstruction in the intake causing the valve to stick open.