Failed intake resonance switchover valve (stuck open or closed, or electrically open/short).; Damaged or disconnected vacuum hose going to the switchover valve actuator.; Corroded, broken, or shorted wiring in the valve control circuit.; Faulty powertrain control module (PCM) driver, though rare.; Carbon buildup or mechanical binding in the intake manifold runner linkage.; Blown fuse or poor ground connection for the valve circuit.

DTC codes / GM codes / P1113

P1113 · GMIntake Resonance Switchover Valve Control

Q: What does code P1113 mean?

Intake Resonance Switchover Valve Control. P1113 on a GM vehicle indicates that the powertrain control module (PCM) has detected a fault in the intake resonance switchover valve control circuit, which is responsible for changing the effective intake runner length to optimize airflow at different engine speeds. The PCM monitors the valve's electrical circuit and commands it to switch states, and when the feedback does not match the expected state, it sets this code.

P1113 on a GM vehicle indicates that the powertrain control module (PCM) has detected a fault in the intake resonance switchover valve control circuit, which is responsible for changing the effective intake runner length to optimize airflow at different engine speeds. The PCM monitors the valve's electrical circuit and commands it to switch states, and when the feedback does not match the expected state, it sets this code.

SystemPowertrain

Code typeGM specific

SeverityLow

Fix difficultyIntermediate

AreaFuel and air metering

Symptoms you may notice

Illumination of the check engine light, often with no other noticeable symptoms.
Slight hesitation or stumble during light acceleration around the switchover RPM.
Reduced engine power or sluggishness at higher engine speeds due to stuck intake runners.
Poor fuel economy if the valve remains stuck in the wrong position.
In some cases, a faint rattle or clicking noise from the intake manifold area when the valve is commanded.

Common causes, most likely first

Failed intake resonance switchover valve (stuck open or closed, or electrically open/short).
Damaged or disconnected vacuum hose going to the switchover valve actuator.
Corroded, broken, or shorted wiring in the valve control circuit.
Faulty powertrain control module (PCM) driver, though rare.
Carbon buildup or mechanical binding in the intake manifold runner linkage.
Blown fuse or poor ground connection for the valve circuit.

How to diagnose and fix it

Verify the code with a scan tool and check for any related codes in the intake and emissions systems.
Inspect the vacuum hoses and electrical connectors at the switchover valve for cracks, corrosion, or looseness.
Test the valve actuator with a hand vacuum pump to confirm it moves freely and holds vacuum.
Measure resistance across the valve solenoid and compare to the manufacturer's specification.
Check for battery voltage and ground at the valve connector with the key on, using a multimeter or test light.
Command the valve on and off with a scan tool to see if the PCM is able to control it and if the valve responds.
If the valve and circuit test good, check the intake manifold for carbon buildup or mechanical binding that could prevent proper operation.

What the intake resonance valve really does

The intake resonance switchover valve changes the effective length of the intake runners to use pressure waves for better cylinder filling at different RPMs, so a failure often causes a subtle loss of low-end torque rather than a hard misfire.
A stuck-open valve can cause a noticeable drop in fuel economy because the engine breathes through the short runners at low speed, reducing volumetric efficiency.
Many technicians replace the valve when the real problem is a cracked vacuum hose or a corroded connector pin that costs far less to fix.
This code can be set by a momentary glitch in the circuit, so always clear the code and test-drive to see if it returns before condemning parts.
On some GM engines, the switchover valve is integrated into the intake manifold and cannot be replaced separately, requiring manifold replacement if the valve fails.

Can I keep driving with P1113?

You can usually continue driving with this code because the engine will default to a safe operating mode, but expect reduced performance and fuel economy. Avoid heavy acceleration or towing until the fault is repaired, and address it promptly to prevent secondary issues.

Tools that help

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Guidance is general and written for GM vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.