75 280Z Hands -Free Fuel Pump Primer Circuit?

[Zed Head]

On 11/24/2023 at 6:02 AM, HusseinHolland said:

I'm going to add a bridge harness to take the AFM pump trigger, run it through the timer relay, then back to the factory relay.  So, I need to extract the trigger wire from the existing relay socket. The constant and switched power for the timer can also be drawn from the main relay, to avoid running lengths of new harness from other sources.

If the goal is to just get a few seconds of power to the pump when the key is turned on you could tap in to the pump power wire anywhere.  It runs down the outside of the floor under the carpet on the passenger side on the 76's.  You could even backprobe the plug, there's a connection there.  That's what I did to power the brake warning check lamp relay.

[HusseinHolland]

3 minutes ago, Zed Head said:

Here's some expensive examples.  Is the goal cheap, effective, or both?

https://www.delcity.net/productsearch?search=time+delay+relay&x=0&y=0&it=

For me, this can be cheap and effective. The point is, wiring is required. Anything remotely plug & play is going to cost more, since you are paying the creator. The only additional element is figuring out the settings for the timer relay.

[HusseinHolland]

57 minutes ago, Zed Head said:

If the goal is to just get a few seconds of power to the pump when the key is turned on you could tap in to the pump power wire anywhere.  It runs down the outside of the floor under the carpet on the passenger side on the 76's.  You could even backprobe the plug, there's a connection there.  That's what I did to power the brake warning check lamp relay.

That's true - much more room to wire over on the pass side. Perhaps I'll just do that. I was planning on just triggering the AFM signal to switch the stock relay. I don't know what load this timer relay can carry, however it should be sufficient to power the pump for a short duration.