Engine Running Rough? Oil in Spark Plug Tubes Could Be the Cause

If your engine is running rough, misfiring, shaking at idle or lacking power, the problem may not always be the spark plugs or ignition coils themselves.

Recently at K Automotive Mechanic Repairs in Derrimut, we inspected a vehicle experiencing a rough-running engine and engine misfire. During our inspection, we found oil inside the spark plug tubes caused by a leaking rocker cover gasket.

When a rocker cover gasket begins to leak, engine oil can enter the spark plug tubes and contaminate the ignition system. This oil contamination can affect spark delivery, causing ignition coils and spark plugs to operate inefficiently, leading to engine performance issues.

Common Symptoms of Oil in Spark Plug Tubes

A leaking rocker cover gasket can cause a range of drivability concerns, including:

• Engine misfire

• Rough idle

• Engine vibration

• Loss of power

• Increased fuel consumption

• Check Engine Light illumination

• Difficult starting

• Burning oil smell

Many drivers first notice the vehicle shaking at idle or feeling less responsive during acceleration.

What Causes a Rocker Cover Gasket to Leak?

Rocker cover gaskets are designed to seal the top of the engine and prevent oil leaks. Over time, heat cycles and age can cause the gasket to harden, crack or lose its sealing ability.

Once this occurs, oil may leak externally or enter the spark plug tubes, where it can affect ignition system components.

Why It's Important to Repair Early

Ignoring a rocker cover gasket leak can lead to:

• Continued engine misfires

• Premature ignition coil failure

• Spark plug contamination

• Reduced fuel efficiency

• Ongoing Check Engine Light faults

Addressing the issue early can help prevent additional repairs and restore proper engine performance.

Professional Engine Diagnostics in Derrimut

At K Automotive Mechanic Repairs, we don't simply clear fault codes or replace parts based on guesswork. We carry out thorough inspections to identify the root cause of engine performance issues and provide clear recommendations backed by photos and videos where possible.

Whether your vehicle has a Check Engine Light, engine misfire, rough idle or loss of power, our team can help diagnose the problem and explain exactly what is required.

Need Help with an Engine Misfire?

If your vehicle is running rough, misfiring or displaying a Check Engine Light, book an inspection with our team today.

K Automotive Mechanic Repairs

📍 18 Star Circuit, Derrimut VIC 3026

📞 0468 963 923

Proudly servicing customers throughout Derrimut, Deer Park, Ravenhall, Truganina, Caroline Springs, Deanside, Sunshine West, St Albans and surrounding western suburbs.

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