Two lanes were closed on the A40 Western Avenue during the Thursday (November 2) morning rush hour after a car caught fire.
Photos show emergency services at the scene in Northolt and thick black smoke wafting up in the air, with cars queuing in traffic.
London Fire Brigade (LFB) was called to the scene on the London-bound carriageway near Polish War Memorial at 7.07am, and had the fire under control just before 7.40am.
It tweeted at 8.15am to report all lanes had reopened.
Motorists on the same stretch of road were stuck in traffic earlier this week when firefighters were called to deal with a huge out of control bonfire (see video at top).
Photos from that incident also showed thick smoke drifting away into he sky.
LFB do not believe there were any injuries.
getwestlondon has contacted London Ambulance Service for further details.
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