1. Vacuum leaks: Check for any loose or cracked vacuum hoses, especially those connected to the carburetor, intake manifold, or transmission modulator. A vacuum leak can cause a lean fuel mixture, leading to sputtering and rough idling when the car is put into gear.
2. Fuel system problems: Check the fuel filter for any dirt or obstructions. Replace it if necessary. Ensure the fuel pump is delivering adequate pressure by performing a fuel pressure test. A weak fuel pump or clogged fuel filter can cause fuel starvation, resulting in sputtering.
3. Faulty ignition components: Check the spark plugs, spark plug wires, distributor cap, and rotor. Look for signs of wear or damage, such as cracks, arcing, or excessive carbon buildup. Replace any defective ignition components as necessary.
4. Transmission issues: If the transmission fluid level is low or contaminated, it can cause the transmission to slip or engage roughly, resulting in sputtering. Make sure the transmission fluid is at the proper level and in good condition.
5. Throttle linkage: Inspect the throttle linkage and ensure it is properly adjusted. A misaligned throttle linkage can cause the engine to run too lean or too rich, leading to sputtering and rough idling.
6. Catalytic converter: A clogged or restricted catalytic converter can cause excessive backpressure in the exhaust system, which can lead to sputtering and reduced engine performance.
It is recommended to perform a thorough inspection and diagnostics on the vehicle to pinpoint the exact cause of the sputtering issue and address it accordingly.
