🚗 Classic Fault — Mercedes-Benz (1968–1976)
W114 250 points ignition advance failure
💰 Estimated Repair Cost
$30 – $120 GBP
Parts and labour estimate
🔧 Tools Required
Timing light, vacuum pump
📋 Overview
The centrifugal and vacuum advance mechanism in the distributor wears on the M114 engine, retarding ignition.
🩺 Symptoms
- Poor performance above 3000rpm
- pinging under load
- poor fuel economy
- engine runs hot
🔍 Possible Causes
- Worn centrifugal advance weights
- seized vacuum advance capsule
- worn distributor shaft bushes
🛠️ Diagnosis Steps
Check timing with strobe at idle and at 3000rpm — advance should increase by 15-20 degrees. Check vacuum capsule holds suction
✅ Most Confirmed Fix
Distributor rebuild or replacement
79% of users confirm this fix worked (15 reports)
🩺 Related Symptoms
🔗 Other Mercedes-Benz Faults
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