Kevman

2004 8.3L V10, drag pack harness from Arrow Racing, and ECM set up for my car.

So.. I have a few issues.. Though I'm skilled in electrical controls.. Automotive baffles me..

I can get the car started on ether only, it won't start on it's own.. That's one issue that Arrow.. And other mechanics I've talked to can't understand.. I have power to the injectors, and it will fire on ether and continue running.. That's issue #1..

Issue #2 is a scary one.. I have two 12VDC interposing relays with 50 micro farad capacitors to cover the delay in the ignition switch, that cycle on 3 relays, ECM Ign, Fuel pump, and the starter.. The starter only being fed from the start portion of the key switch. The ECM Ign, and fuel pump relay shut off when the switch to off.

The issue is, when all three of those relays are off, the engine will continue to run until the fuel pressure drops off..

I have tested this with the engine running, shut the key off, and the relays are confirmed to be in an off state.

I have 6 wires from the ECM, I've spent countless hours surfing prints, and correspondence with Arrow Racing..
+12 -> Constant ECM power
Z12 -> ground for the injector loop
A0 -> Ignition +12
K125 -> Alt. loop
K125A -> Alt. loop
Tach -> well.. Tach..

bigal55

iTrader: (1)

I kind of understand your problem, but without circuit diagrams, there really is no way to answer your questions. I do have a question of my own though, why do you need the delays from ECM ignition to fuel pump to starter? Sounds like you don't have a cold start enrichment system thus the no start unless ether is used to enrich the charge. The run on after key off is an ignition problem, the distributor/dis modules are not being turned off. Why? Could be the ECM or possibly the caps are holding the relays on? Are you sure there is no power passing through the load side of the relays? I see you have quite a few posts so I think you will probably be forgiven about the not being a third gen. Post some circuit drawings and I'm sure someone can make heads or tails out of them. GL!

Kevman

Well that's the thing, they gave me a 1200 page PDF of Viper BCM and PCM prints.. Which help for chasing wires.. But to compare it to what I actually have...

I solved the issue.. I think it had to do with the intake being completely dry of fuel, and that was due to it dying when the fuel pump would cut out, and the engine would still run..
There's a relay coming off of the ECm that was for the BCM.. Sort of like a switch to say the alarm.. And everything was okay before allowing the car to start.. I wired that coil on the relay through another relay normally open contact, controlled by my ignition/run circuits.. It shuts off now, and fires right up without hesitation.

bigal55

iTrader: (1)

That's great! Good to hear it's running, sounds like a cool mix. I always liked the early Chargers, and a Viper V10! Woot Woot!