✅ Fixed
Cleaned MAF sensor with dedicated MAF cleaner spray. Also found small cracked vacuum hose near intake manifold. Replaced hose $8. P0171 cleared and has not returned.
Mercedes-Benz CLA 2018 Check engine light P0171 lean mixture
On This Page:
🔍 Symptoms
⚙️ Causes
🔧 All Repairs
⚠️ Avoid These
🧾 Driver Reports
🔗 Similar Faults
🩺 Related Symptoms
📖 Repair Guides
⚡ Quick Summary
Severity Level
High
Safe to Drive?
⚠️ Drive with Caution
Safety Impact
Can become a safety issue if left unresolved
Urgency Level
🟠 Fix Soon
Mercedes-Benz CLA 2018 check engine light on with P0171 lean bank 1 code. Rough idle and slightly worse fuel economy noticed. 118984 km. This fault code is stored when the engine control unit detects a specific fault condition. Common causes include sensor failures, wiring faults, and component wear. Always read additional fault codes before replacing parts — multiple codes together provide a clearer diagnosis. Clear the code after repair and test drive to confirm the fault does not return.
🔍 Symptoms
📍 Check engine light — P0171 lean code
📍 Mercedes-Benz CLA
⚠️ P0171 fault code
⚙️ Possible Causes
Fault code P0171 detected
Check engine light — P0171 lean code
Mercedes-Benz CLA
Possible: Cleaned MAF sensor with dedicated MAF cleaner spray. Also found small cracked vacuum hose near intake manifold. Replaced hose $8. P0171 cleared and has not returned.
Repair / Solution
Based on 107 driver confirmations
⚠️ Wrong Diagnosis?
No commonly reported misdiagnoses for this fault yet. If you have replaced a part that did not fix this Mercedes-Benz 2018 problem, submit a wrong diagnosis report — it helps other drivers avoid the same costly mistake.
🧾 Driver Reports
🚗 More About This Vehicle
Explore more Mercedes-Benz models
📖 Related Repair Guides
Help other owners by sharing your experience.
Your real-world fix helps thousands of drivers worldwide. Takes 2 minutes.