🚗 Classic Fault — Mercedes-Benz W126 (1979–1991)
W126 automatic transmission 722.3 second gear start
💰 Estimated Repair Cost
$20 – $80 GBP
Parts and labour estimate
🔧 Tools Required
Vacuum pump, spanners
📋 Overview
The 722.3 automatic gearbox can start in second gear when the modulator fails, causing sluggish acceleration.
🩺 Symptoms
- Car pulls away in second gear rather than first
- sluggish acceleration from rest
- gearbox feels lazy
🔍 Possible Causes
- Failed vacuum modulator
- incorrect TV cable adjustment
- worn gearbox
🛠️ Diagnosis Steps
Test vacuum modulator — should hold vacuum. Check TV cable adjustment at gearbox.
✅ Most Confirmed Fix
Vacuum modulator replacement and TV cable adjustment
83% of users confirm this fix worked (21 reports)
🔗 Other Mercedes-Benz W126 Faults
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