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P1245

Intake Plenum Switchover Valve.

  • GM
  • Powertrain
  • Manufacturer code
  • Low severity

How this code is built

P
SystemPowertrain
1
Defined byThe manufacturer
2
AreaFuel and air metering (injector circuit)
45
FaultThe specific fault in that area

What it means

On GM vehicles P1245 relates to the intake plenum switchover valve, a control that changes the intake manifold or plenum between two operating modes to suit engine speed and load. The engine control module has detected a fault in the valve's circuit or its operation, so the switchover is not behaving as commanded. The exact fault conditions and the way the system is built depend on the model and engine.

Symptoms

  • Malfunction indicator lamp on
  • Loss of power at certain engine speeds
  • Flat spot or hesitation when accelerating
  • Rough or unstable idle
  • Poorer fuel economy

Possible causes

  • Faulty or sticking switchover valve actuator or solenoidlikely
  • Damaged, chafed or corroded wiring or connector to the valvelikely
  • Leaking, split or disconnected vacuum hose or vacuum reservoir, where the system is vacuum operatedpossible
  • Plenum flap or linkage seized, broken or carbon-cloggedpossible
  • Blown fuse or poor power or earth supply to the valve circuitpossible
  • Fault within the engine control module driver circuitrare

How to diagnose

  1. Read all stored and pending codes and record the freeze frame data to see the engine speed and load when the fault set
  2. Check for related codes and for any technical service bulletins for the specific model and engine
  3. Visually inspect the valve, its wiring and connector for damage, corrosion, chafing or water ingress
  4. Inspect vacuum hoses, any check valve and the reservoir for cracks, splits or disconnection, if the system is vacuum operated
  5. Check the fuse and the power and earth supplies at the valve connector with a multimeter
  6. Measure the valve or solenoid resistance and compare it with the manufacturer specification for the engine
  7. Command the valve with a scan tool and watch or listen for movement, checking that the linkage or flap moves freely
  8. Check the control wire for continuity and for shorts to earth or supply back to the control module

How to fix

  • Replace the switchover valve or actuator if it is faulty or sticking
  • Repair or replace damaged wiring or connectors, and clear any corrosion
  • Replace perished or leaking vacuum hoses, the check valve or the reservoir
  • Free off or replace a seized plenum flap or linkage, and clean any carbon build-up as the manufacturer advises
  • Restore a blown fuse after finding the cause of the failure, and repair any poor power or earth supply
  • Only after all other causes are ruled out, diagnose the control module driver and repair or replace it as required

Can I keep driving?

Low severity

The car can usually be driven in the short term, but expect reduced performance and economy. Book it in soon so that a minor fault does not hide other problems.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.

This code for other makes

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