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140 Fuel injector polarity

Do Bosch Fuel Injectors have a positive and a negative terminal ?
- I do not see any +/- markings.
- Or can they connected either way?
I'm am rebuilding the wire harness on my 73 Volvo 164.
Thanks,
Kevin

Comments

  • Generally efi injectors don't care about polarity as they are just a solenoid
  • You can always test them with a 1.5V dc power supply. I'd expect them to be directional as they are an electro-magnet designed to lift the pin against a spring. Hence the coil will obey the right hand rule.
  • You can always test them with a 1.5V dc power supply. I'd expect them to be directional as they are an electro-magnet designed to lift the pin against a spring. Hence the coil will obey the right hand rule.

    Most people reasonably assume this but, like a solenoid, driving current through the winding causes the plunger to move toward the magnetic field, i.e., into the region enclosed by the winding. Reversing the polarity of the applied voltage does not reverse the direction of movement, because a typical plunger is just a piece of metal (not a magnet), and thus it is always attracted to (not repelled from) the magnetic field.
    If there's no positive or negarive markings it doesnt matter.

    Try Ians suggestion test leads with a 9v battery and you will find it fires normally either way you connect the polarity

  • After finishing the wire harness, I’ll try to connect the injectors the way they were before disassembly. So far 2 votes for no polarity and 1 for. Any other thoughts on the connection?

    Here’s a pic of the progress:
    a59714s7naot.jpeg
  • Whilst polarity doesn't matter it is convention to run +ve to pin 1 and good practice to wire them all with the same polarity. Especially for older injectors.

  • Try Ians suggestion test leads with a 9v battery and you will find it fires normally either way you connect the polarity

    NOOOOOOO NOT 9V! D-Jet is strictly 1.5V. You won't have an injector at 9V.
  • Thanks everyone for the input - the wire harness has been installed it worked 1st try!!!
    There were no polarity issues - it did not matter which way the injector connectors were connected. (hahaha)
    Kevin
  • jamesincJames (@jamesinc) Oz Volvo Ice Fortress
    Thanks everyone for the input - the wire harness has been installed it worked 1st try!!!
    There were no polarity issues - it did not matter which way the injector connectors were connected. (hahaha)
    Kevin
    That's impressive! Good work
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