Waveforms

Fuel pump

Applications:

  • main fuel pump for fuel injected engines;
  • low pressure or lift pump for direct injection engines;
  • lift pump for diesel engines.
Voltage and current waveforms of a properly functioning fuel pump
Voltage and current waveforms of a properly functioning fuel pump

Voltage and current waveforms of a properly functioning fuel pump. Engine start and running at idle.
1 – supply voltage;
2 – current of the fuel pump.

Voltage and current waveforms of a malfunctioning fuel pump
Voltage and current waveforms of a malfunctioning fuel pump

Voltage and current waveforms of a malfunctioning fuel pump. Engine start and running at idle.
1 – supply voltage;
2 – current of the fuel pump.

Examples of current waveforms of malfunctioning fuel pumps with poor contact between brushes and commutator
Examples of current waveforms of malfunctioning fuel pumps with poor contact between brushes and commutator
Examples of current waveforms of malfunctioning fuel pumps with poor contact between brushes and commutator

Examples of current waveforms of malfunctioning fuel pumps with poor contact between brushes and commutator. Engine is running at idle.

Voltage and current waveforms of a malfunctioning fuel pump, the armature is seizing.
Voltage and current waveforms of a malfunctioning fuel pump, the armature is seizing.

Voltage and current waveforms of a malfunctioning fuel pump, the armature is seizing. The current going in to the pump increases and results in overload, burned relays and connectors as well as fuses blowing.
1 – supply voltage;
2 – current of the fuel pump.
A – engine start;
B – point in time where the fuse blew.