DVSA detected exhaust leakage (cracked pipe, loose joint, corroded silencer, damaged catalytic converter). Exhaust leaks bypass emissions control, risk toxic gas entry into cabin, and can become dangerous defects if dragging. Fix within 4–8 weeks.
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Check Your MOT HistoryQuick answer
Exhaust leaks are major advisories with escalation risk. A dragging exhaust is a dangerous defect. Fix within 4–8 weeks. Repair typically costs £150–£400, but catalytic converter damage can exceed £800.
Exhaust leaks are major advisories that escalate if ignored. A minor leak becomes a dragging exhaust (dangerous defect). Leaks bypass emissions control and risk toxic fumes entering the cabin.
Minor leak (hissing sound)
Repair within 4–6 weeks. Likely MOT failure on retest if not fixed. Safe to drive short distances.
"Insecure" means it's at risk of dragging. Don't ignore—this is how minor leaks become dangerous defects.
Exhaust clamp/strap: £30–£60
Pipe welding/repair: £100–£200
Silencer replacement: £120–£280
Full exhaust system: £250–£500
Catalytic converter: £300–£800+ (varies by vehicle)
Independent garages 30–40% cheaper than dealerships. Cat converter theft risk on some models—consider aftermarket protection.
If your exhaust is hanging down and dragging on the road, this is a dangerous defect. Do not drive — it creates a spark/fire hazard. Have it repaired or strapped up immediately.
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Check MOT HistoryLast reviewed: July 2026 · MOT data sourced from DVSA · Editorial Policy