Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the engine is having trouble mixing the right amount of air and fuel in cylinder 5. It's getting too much air or not enough fuel, which isn't good for the engine.
The engine control module (ECM) has detected an imbalance in the air-fuel ratio for cylinder 5, indicating that the mixture is too lean (more air than fuel).
The P11D8 code is triggered when the ECM identifies that the air-fuel mixture in cylinder 5 is too lean. This can be due to several factors such as a vacuum leak, faulty injector, or a malfunctioning sensor. The imbalance can lead to poor engine performance and increased emissions.
• Check Engine Light is on
• Rough engine idle
• Decreased fuel efficiency
• Engine misfires
• Poor acceleration
• Vacuum leak near cylinder 5
• Faulty fuel injector for cylinder 5
• Malfunctioning oxygen sensor
• Fuel pressure issues
• Exhaust leak near the manifold
ECM: Engine Control Module
Lean Condition: A situation where there is too much air and not enough fuel in the air-fuel mixture
• Use an OBD-II scanner to confirm the code and check for other related codes.
• Inspect the vacuum lines and intake manifold for leaks.
• Test the fuel injector for cylinder 5.
• Check the oxygen sensors for proper operation.
• Measure the fuel pressure to ensure it is within specifications.
• Repair or replace any vacuum leaks.
• Replace the faulty fuel injector.
• Replace the oxygen sensor if it is malfunctioning.
• Fix any exhaust leaks.
• Ensure the fuel pressure regulator is functioning correctly.
• OBD-II scanner
• Fuel pressure gauge
• Vacuum leak tester
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Chevrolet Silverado
• GMC Sierra
• Cadillac Escalade
• Regularly maintain the fuel system.
• Check and replace air filters as needed.
• Inspect vacuum lines for wear and tear.
Engine Performance
• Avoid driving the vehicle until the issue is fixed to prevent further damage.
• Schedule a diagnostic check with a professional mechanic.
Check your vehicle's warranty to see if engine repairs are covered.
This code has been associated with lean conditions in specific cylinders and is often linked to fuel system or sensor issues.
Moderate – It should be addressed soon to prevent engine damage.
Driving with a lean condition can increase emissions and may not pass emissions testing.
• Engine at operating temperature
• Vehicle at idle
Cylinder 5 is located on the engine block, typically on the right side for V-type engines.
Q: Can I drive with a P11D8 code?
A: It's not recommended to drive with this code as it can lead to engine damage.
Q: What happens if I ignore the P11D8 code?
A: Ignoring this code can result in poor engine performance and potential damage over time.
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Fitment Required · Vehicle-fitment part
Relevant when the code or supporting diagnostics point toward upstream or downstream oxygen-sensor faults.
This code family often involves upstream or downstream oxygen-sensor diagnosis.
Verify exact sensor position and vehicle fitment before buying.
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Fitment Required · Vehicle-fitment part
Commonly relevant for misfire, ignition-efficiency, and some drivability-related repairs.
Misfire and ignition-related faults commonly involve spark plugs as part of the repair path.
Check the correct plug type, gap, and engine application for your vehicle.
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Fitment Required · Vehicle-fitment part
Relevant when the fault points toward ignition-coil performance or cylinder-specific ignition issues.
Some ignition faults involve coil performance or cylinder-specific coil problems.
Match the coil to your engine and confirm the failed component before ordering.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.