I have purchased a Fuel Injector Flush Cleaner Adapter DIY Kit on eBay:

https://www.ebay.com/itm/Vehicle-Fue...72.m2749.l2649


What is the voltage applied to the injectors in normal operation?

I was told that not all fuel injectors are applied 12 volt pulses, with some could be applied with much lower voltage. If the injectors are of lower voltage and I were to apply a 12 volt to them I could damage the injectors' coils.

Better asking first before doing anything stupid like applying a wrong voltage.