The carburettor regulates the flow of fuel and air to an engine. Many modern vehicles have eliminated carburettors in favour of direct fuel injection controlled by a computer. Older vehicles with carburettors require maintenance and cleaning to keep fuel and air flowing correctly. Popping noises from a carburettor indicate a form of backfire.
Fuel To Air Mixture Is Too Lean
Too much air and not enough fuel causes backfires to occur in the intake manifold. The exploding mixture then vents through the carburettor. Improper carburettor adjustments or vacuum leaks can cause this condition.
Improper Ignition Timing
The ignition system controls the delivery of the spark from the electrical system to the spark plugs. These sparks must be sent at the correct time. If the timing is off the engine idles rough and backfires occur. Use a timing light to check the ignition timing according the vehicle's specification. The distributor needs adjustment to correct the timing.
Fuel System Problems
A clogged fuel filter or faulty fuel pump can cause issues with fuel delivery. This results in a fuel mixture that is too lean for the engine and results in backfires through the carburettor.