Depends on specific engine... could be any if the following. Not all for all engine types.
Spark plugs Ignition coil, coil pack, or Coil Over Plug Plug wires, distributor cap, cap and rotor Fuel Fuel injectors Ignition control module / PCM Various wiring interconnections.
Start with scheduled maintenance for ignition components, i.e. spark plugs, wires, cap, and rotor depending on engine.
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Depends on specific engine... could be any if the following. Not all for all engine types.
Spark plugs
Ignition coil, coil pack, or Coil Over Plug
Plug wires, distributor cap, cap and rotor
Fuel
Fuel injectors
Ignition control module / PCM
Various wiring interconnections.
Start with scheduled maintenance for ignition components, i.e. spark plugs, wires, cap, and rotor depending on engine.
Plug , coil or injector or in the pcm