Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's engine is trying to save fuel by turning off some cylinders, but it's not getting enough fuel on one side of the engine.
When the engine deactivates some cylinders to save fuel, it might not get the right amount of fuel and air, causing it to run 'lean' on one side.
The P2E68 code indicates that the engine control module (ECM) has detected a lean air-fuel mixture condition on bank 1 during cylinder deactivation. This means there is too much air and not enough fuel being delivered to the engine cylinders that are still active, potentially leading to poor performance and increased emissions.
• Check Engine Light is on
• Reduced engine performance
• Increased fuel consumption
• Vacuum leak in the intake manifold
• Faulty fuel injectors
• Exhaust gas recirculation (EGR) valve malfunction
Lean: A condition where the air-fuel mixture has too much air and not enough fuel.
Cylinder Deactivation: A technology that turns off some cylinders in an engine to save fuel.
• Use an OBD-II scanner to confirm the code.
• Inspect the intake manifold for vacuum leaks.
• Check the operation of the fuel injectors on bank 1.
• Repair or replace any vacuum leaks found.
• Clean or replace faulty fuel injectors.
• Inspect and repair the EGR valve if necessary.
• OBD-II scanner
• Vacuum gauge
• Fuel injector tester
$150 - $500
Moderate
• Chevrolet Silverado
• GMC Sierra
• Cadillac Escalade
• Regular maintenance of the fuel system
• Check for vacuum leaks periodically
• Ensure the EGR system is functioning properly
Engine Performance
• Avoid aggressive driving until the issue is fixed.
• Get the vehicle inspected by a professional mechanic.
Check with your vehicle manufacturer for specific warranty coverage related to engine components.
This code has become more common with the introduction of cylinder deactivation technology aimed at improving fuel efficiency.
Moderate – Should be addressed soon to avoid potential engine damage.
Ignoring this code may lead to increased emissions, which could be in violation of local environmental regulations.
• Engine at operating temperature
• Vehicle driven under normal conditions
Bank 1 refers to the side of the engine with cylinder 1, typically the driver's side in a V-engine configuration.
Q: What does 'lean' mean in this context?
A: Lean means there is too much air and not enough fuel in the engine's air-fuel mixture.
Q: Can I drive with this code?
A: It's possible to drive short distances, but it's best to get it fixed soon to avoid further issues.
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