PCV Valve Malfunction

The Positive Crankcase Ventilation (PCV) valve can fail, leading to increased oil consumption, rough idling, and potential vacuum leaks. Early detection and replacement are key to preventing further engine issues. Estimated repair cost: $300 - $700.

Leaks can develop from the coolant expansion tank, hoses, or water pump. These leaks can lead to engine overheating if not addressed promptly. Estimated repair cost: $400 - $1000.

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2018 Audi A4 Maintenance guide

Name: Maintenance dataset for 2018 Audi A4
Creator: Carfocal

v1.0Updated Jun 2, 2026Ethan Miller4 Sources Analyzed1 Critical Recalls

MAINTENANCE SUMMARY

The 2018 Audi A4 requires diligent attention due to a significant number of Technical Service Bulletins (TSBs), indicating potential underlying issues. Owners should prioritize ensuring recall 21V874000, concerning the passenger airbag system, is completed.

View Critical Issue: Passenger Occupant Detection System (PODS) Fault

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Reliability Score

Est. Annual Maintenance Cost

$500 - $800

TSBs & Recalls

136 TSBs | 2 Recalls

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Key Takeaways

Proactive maintenance is essential given the 136 TSBs.
Address the critical airbag system recall (21V874000) promptly.

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Critical service intervals

Common failure analysis

Symptoms and prevention guidance