1. Ignition Problems: Issues with the ignition system, such as faulty spark plugs, worn-out spark plug wires, or a malfunctioning ignition coil, can prevent cylinders from firing properly.
2. Fuel Delivery Issues: Problems with the fuel injection system, such as a clogged fuel injector or a faulty fuel pump, can lead to insufficient fuel delivery to certain cylinders.
3. Engine Compression Issues: If the engine has low compression, particularly in two of the cylinders, it can affect their ability to generate sufficient power. Compression issues can be caused by worn piston rings, damaged valves, or a cylinder head gasket leak.
4. Vacuum Leaks: Vacuum leaks can cause rough idling and engine performance issues. If there's a significant leak near one or two of the cylinders, it can impact their proper operation.
5. Computer Issues: Modern cars rely on engine control units (ECUs) to manage engine functions. A malfunctioning ECU or faulty sensors can result in the engine running on a reduced number of cylinders.
6. Camshaft or Crankshaft Problems: Issues with the camshaft or crankshaft, which are responsible for the valve opening and closing mechanism, can affect cylinder performance.
Identifying the root cause of the issue requires proper diagnostics. If you suspect that your car is running on only two cylinders, it's advisable to have it inspected by a qualified mechanic or automotive technician. They can perform tests to pinpoint the exact cause and recommend the necessary repairs.
