Cylinder 7 Deactivation Solenoid Control Circuit Open
The P2666 code means the vehicle's onboard diagnostic system has detected: Cylinder 7 Deactivation Solenoid Control Circuit Open. This is a moderate severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- hard
- Estimated cost
- $300 - $2500 (parts and labor)
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Common Symptoms
- Check Engine Light on
- AFM/DFM/MDS system fault
- Cannot enter fuel saving mode
- Possible lifter collapse symptoms
- Engine roughness intermittently
Probable Causes (Ranked by Likelihood)
- Open circuit to cylinder 7 solenoid Very High
- Collapsed AFM lifter on cylinder 7 High
- Worn solenoid connector pins Moderate
- ECM driver failure Low
Step-by-Step Diagnostic Procedure
-
Read freeze frame data and confirm P2666 is present
-
Test solenoid coil resistance
-
Check for collapsed lifter by performing cylinder leak-down test
-
Inspect connector pins for wear or corrosion
Frequently Asked Questions
What does P2666 mean?
P2666 indicates a problem with the cylinder 7 deactivation solenoid control circuit open. This affects the vehicle's ability to deactivate cylinders for improved fuel economy.
Can I drive with a P2666 code?
You can drive short distances. The cylinder deactivation system will be disabled, reducing fuel economy. Have it checked to prevent potential lifter damage.
How much does it cost to fix P2666?
Repairs typically cost $300 - $2500. Simple solenoid replacement is less expensive, but collapsed lifter repair can be $2,000 or more.
Sources
This page is built from documented references. Verify against your own service info before repair work.
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