s14 ka24de wiring specialties standalone harness help
 

Hey everyone,

has anybody installed the standalone ka24de harness from Wiring Specialties in their s14? Everything seems plug and play, where i'm getting hung up on is the "flying leads" that are included with the harness. These leads trigger certain things like start signal, ecu power, fuel pump, etc...

Anyways, from what I have been told by the guys at Wiring Specialties, is that the fuel pump trigger wire coming from the flying lead acts as a ground trigger source for the fuel pump relay. I had completely gutted my car and rewired the chassis with a custom relay panel and am certain all my wiring is accurate, except the fuel pump still won't prime.

My question is this: is there anything wrong with wiring the isr 255 pump straight to a switch through a relay, eliminating the ground trigger wire altogether? This would mean the pump gets turned on before startup and turned off after shutdown manually. The only reason i can think that this ground trigger wire would be needed is to send a signal to the fuel pump to prime for a couple seconds once the ignition is turned on.

Hope my question/concern is understandable...been breathing in too many gas fumes today I suppose. :hs:

No there is no problem hard wiring the fuel pump thru a relay and a switch

I figured it would be fine, just making sure that lead on the harness won't be needed for anything other than just signaling the fuel pump to turn on. Thanks for affirming my thoughts!

You can also call and ask questions, I talked to Uri in TS and he was helpful

The main reason for having the fuel pump under ECU control is so the fuel pump gets shut off when either the ignition key is turned off or the engine stops turning. An accident could get very ugly if the fuel pump kept running if you were unable to turn it off manually. Something to think about.

So why are pro racecars wired seperate switch?

Good question! Pro racecars are operated in controlled environments with safety personnel with fire extinguishers, special training, etc. All racecars are required to have a master kill switch that shuts off everything, reachable from outside the car. On the road is a bit different.

Great answer!