Smoke was seen billowing over the A720 after the silver BMW caught fire on the eastbound carriageway at the Lasswade slip road just after Gilmerton at about 12.45pm.
Heavy traffic soon built up back to the Sheriff Hall roundabout as police attended with no reports of injuries.
Police Scotland tweeted: “Reports of a vehicle on fire on the A720 Edinburgh City Bypass at the Lasswade off slip eastbound. Traffic already backing up. Police are in attendance.”
Drivers reported long delays. Sara Jones tweeted: “Breakdown on A720 just after Gilmerton causing queues blocking lane one.”
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