EFI power

-
Backally

Backally

FABO Gold Member
FABO Gold Member
Joined
Sep 4, 2011
Messages
631
Reaction score
401
Location
Wisconsin
A0608DC7-57CE-4071-88D1-66E147EC5AEB.jpeg
I asked this in a roundabout way on a previous thread, so want to clarify I’m not screwing up. Need power to Holley Sniper, 12v while cranking and running. Supposed to draw less than 3 amps. I put a jumper off the blue and brown wires on the steering column connector. See the pink wire in the photo. Now read something that suggests putting a diode in there somewhere to prevent “back feed”. Don’t know squat about diodes, and not the sharpest on electric in general. So is what I have done going to cause issues? I have headlights and electric FP on relays, and Crackbacks alt-Batt connection. Bulkhead connector has been disassembled and is in good shape.
 
Cant remember where i spliced mine in but it just needs to be tapped into a good spot that has 12vdc constantly when the starter is trying to turn over and then 12vdc continous there after. Id just view whatever ignition source your using with a voltmeter while starting the starter and make sure the voltage doesnt go away. I didn't have to mess with any diodes.
 
Thx. it starts and runs, haven’t driven much yet but concerned I’m causing a problem elseware in the electrical or ignition system
 
You cannot just jumper those two wires UNLESS you have installed an ignition system which does away with the ballast resistor.

If that is the case then you are fine.
 
Nope, still got the ballast. What can I do to fix this? And just to add to my knowledge base, what happens with it as is?
 
Another thing you want to check "in general" if you still have an 3 or multi wire alternator / regulator setup and not a "1 wire"

That is to check your running/ charging battery voltage. Once the battery/ engine is warmed up and the battery "normalized" be sure charging voltage at simulated "low to medium cruise" RPM is not more than a bout 15. "Normal is 13.8--14.2. If this is high you likely have voltage drop in the "ignition run" circuit. You can check this by putting one probe of your meter on battery + directly, the other probe on your ignition "run" in the engine bay, and turn the key to "run." You are hoping for a very low reading, the lower the better

More than say .3V (3/10) I would check the path back to the battery. Also be certain the VR is well grounded, and has a good ground path to battery NEG
 
I went thru this issue on my Sniper. No matter where I tied into the ignition switch I would lose power momentarily either from the run to start position or the start back to run. Just the swapping of the contactor in the switch to the contacts was enough to interrupt power. This would cause the efi to reboot. I ended up with a hidden switch tied directly to the battery buss off the fuse box. I could find no where downstream of the ignition switch that didn’t cause this. My system does not use a ballast resistor and I do have the blue and brown ignition wires tied together and still had this issue. Tried a remote relay etc. My bottom line was what I believe is the spacing of terminals in the ignition switch is enough to interrupt power. This is on my 71 Demon.
 
Dubob said:
I went thru this issue No matter where I tied into the ignition switch I would lose power .
Click to expand...


It may be your switch is "iffy" and it might be the later models are different. My 67 worked fine this way with Holley pro-jection, then Commander 950, then Holly HP LOL. Many others do this and it works. You "could get tricky" with a relay/ transister / etc timing circuit. Another "work around" would be to simply use a push button starter switch, and leave the key in "run"
 
67Dart273, yes sir. But this was the second new switch. “ new parts aren’t always good parts” to quote a knowledgeable guy. The hidden switch adds a piece of mind for me “security” as much as it is.
 
67Dart273 said:
Another thing you want to check "in general" if you still have an 3 or multi wire alternator / regulator setup and not a "1 wire"
Click to expand...

I got the 3 wire. Will test voltage as you suggested, but haven’t had any issues so far. Sniper has a voltage readout and if anything it seems low but I haven’t driven it much to see where it stabilizes

Dubob said:
I went thru this issue on my Sniper. No matter where I tied into the ignition switch I would lose power momentarily
Click to expand...

I haven’t had that problem. Started probably a dozen times and it hasn’t dropped off so far. I do have a easy remote switch I could connect if that shows up.
 
Does "EFI Power" mean that your engine now has "electronic fuel injection" and you need power for it? If so, you should install a 30 A relay which is triggered off IGN + IGN2 power to supply current direct from the battery. The kit's manual should detail this, and most include a relay.
 
The main power for my Holley Sniper comes directly off the battery, and does have a 30a fuse, with a relay to the fuel pump. This pink wire powers the ecu, which I was told was less than 3a. I tapped into the ign1 and ign2 at the steering column connector to power that.
 
That is a "trigger wire" much like a relay coil or the "small red" on an MSD Does not need much current
 
You must log in or register to reply here.
-

Back
Top