What Causes Black Smoke from Car Exhaust?

1 Answers
LeKate
07/29/25 9:03pm
Black smoke from the exhaust pipe is caused by incomplete fuel combustion. This may be due to faults in the fuel supply system, insufficient air intake caused by blockages in the intake and exhaust systems, among other reasons. Fuel supply system faults: Starting system faults preventing the engine from turning or turning too slowly may be due to insufficient battery charge, loose or severely oxidized battery terminal clamps; blown main circuit fuse; ignition switch failure; starter motor failure; open circuit in the starting wiring or poor connector contact. Insufficient air intake caused by blockages in the intake and exhaust systems: This is mainly due to excessive valve clearance. When the valve clearance is too large, it results in insufficient engine air intake and incomplete exhaust. This leads to incomplete fuel combustion, subsequently causing black smoke from the exhaust pipe.
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