Flames quickly engulfed the sedan in front of the BP station just after the Sterling Boulevard entrance to the highway, sending plumes of black smoke skyward, shortly after 2:30 p.m.
Englewood firefighters doused the blaze while eastbound Route 4 remained closed at Webster Avenue.
Traffic quickly backed up toward Hackensack while rubberneckers slowed the flow on the westbound side.
No injuries were immediately reported.
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