Is it safe to drive with Mercedes C-Class Exhaust Rattle Cold — Catalytic Substrate?

Generally safe to drive for short distances, but the fault should be diagnosed and repaired promptly.

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Mercedes C-Class Exhaust Rattle Cold — Catalytic Substrate — Mercedes-Benz C-Class 2007 | MyCarFault

Mercedes C-Class Exhaust Rattle Cold — Catalytic Substrate

Mercedes-Benz C-Class 2007 All

Safe to Drive?

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Urgency Level

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A rattling from the exhaust on cold startup that disappears when warm on W204 C-Class indicates a broken catalytic converter substrate. The ceramic substrate cracks and rattles until it expands and jams. P0420 may or may not be stored. Cat replacement costs £200-500.

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Mercedes C-Class Exhaust Rattle Cold — Catalytic Substrate

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