[304065]

Ladies and Gentlemen:

I'm getting down to the final stages of my fuel pump install and have a couple questions re: wiring of relays:

1. Someone recommended that I wire the "Hot" or +12v to terminal 87 of the relay (the normally open contact) rather than to terminal 30, so that when the relay is de-energized, current won't flow across to terminal 87a (the normally closed contact)-- because if anything contacts 87a, even though it's not being used, it could cause a short. I doubt this is really relevant and PORSCHE does it opposite, e.g. the factory wiring diagrams show +12v to terminal 85 and then over to terminal 30.


2. The same source recommended that I use a "Quench" diode in parallel with the relay coil (that is, parallel to terminals 85 and 86) in order to prevent a backwards voltage through the circuit when the energizing current is shut off and the field breaks down. Just like an ignition coil. . . does this really matter? And which end of a diode is the positive end, is it the one with the stripe?

These types of questions are so obscure that I would ask them ONLY to this board. . . the quantity and quality of automotive knowledge here continues to blow my mind.