Full Size Jeep Network

Hi everyone,

After a year sitting and getting the Jeep together again I got it fired up on a 2bbl sniper with ignition box and distributor. It’s all hooked to a keyed ignition that went to the old ignition box. The sniper turns on and off as it should with just battery power.

However once it was actually fired up and running the key is unable to shut it off and I have to disconnect power to the ignition box to get it to stop running.

Has anyone experienced this? Both my pink wires and red for the ignition box all go to the same switched ignition.


Sent from my iPad using Tapatalk

Sounds like the alternator is feeding in some place past the ignition switch.

Or the switch itself is bad maybe?

If the engine isn't running, and you turn the switch to run, and then back to off, does the sniper still have power going to it? If not, its probably the alternator back feeding some place.

This should work


Sent from my iPhone using Tapatalk

Sent from my iPhone using Tapatalk

Long past this post ... however, I've seen this problem before. Originally, power for the module and the coil comes from the ignition switch. There is a resistance wire in-between the ignition switch and the alternator exciter connection on these Jeeps. This blocks the back feeding from the alternator to the ignition switch enough to shut off the original ignition in the Jeep.

With a system like the Sniper, it uses the ignition connection only as an on-off signal, and has a separate battery connection that supplies power to run the control unit. The trickle of current back through the resistance wire is enough to keep the Sniper switched on. A diode will block that signal completely.

I’m even later than all of you! Work has been wild, thank you for this. I’m diving back into the Wagoneer again sorting out a transmission issue. As soon as it’s back up I’ll be testing this!

Thank you everyone!


Sent from my iPhone using Tapatalk

Just for everyone’s awareness, I installed a plug and play diode for GM alternators I found on summit. Worked great. Thanks for everyone’s help


Sent from my iPhone using Tapatalk

Glad you got it figured out!

I had this same issue. I wired both pink wires (one from sniper throttle body and one from hyperspark 3 pin harness) up to one of the old coil wires (yellow wire in picture below) and I had to cut the throttle body pink wire to turn it off, disconnecting the battery didn't shut it off. So now I only have the hyperspark pink wire connected to the old coil wire. However, I'm having issues finding a good spot to connect the other pink wire that requires a dedicated run and start location. According to the holley install video I watched both pink wires can go to the same switched 12v source. I tried a spot where the chime module used to be that showed 12v on run and 9v on start/crank. But, it appears that there is a drop between run and start as the screen restarts when you crank on the handheld. Also if I turn off the ignition it keeps running and I have to pull the wire. Can someone post a picture of where they spliced in their pink wires for the sniper.

I have read posts that mention a red wire (which I can't find) and others mention the yellow wire which is what I think I used initially.
I'm also betting that I have the issue of backfeed from the the alternator that might have been the reason I couldn't shut the engine off when I originally had both pink wires connected to the yellow wire that went to the original coil.

Also to add an additional question, what in-line diode is recommended for blocking the backfeed from the alternator, I've seen a post with a radio shack part number but we don't have them here anymore, instead of a part number can someone give the specs and I'll try and see what I can find locally.

See attached image of where the first pink wire is connected to old coil connection
Thanks for all the help.

Update: Napa says my alternator regulator is bad and I need a new alternator because there should not be a backfeed. Is this napa trying to sell me a part or an legitimate fix? The alternator is old.

your getting a back feed from somewhere on the regulator firing the ignition. Whether its faulty or there are other issues, its hard to say with the info that is presented.

I installed a 6A05 diode that came in a 5 pack from Amazon and it worked great. Need to solder it but I installed it inline on the thin solid wire off the alternator 2 prong plug and now have no issues.

The thin solid wire is nichrome, like the resistance wire that glows red in a toaster. I've tried soldering to these and failed. With the diode in there, you can replace the nichrome resistance wire with plain stranded copper primary wire and it will solder easily and work fine. The diode takes the place of the resistance wire.

Theduke wrote: ↑Fri Nov 04, 2022 7:04 am Update: Napa says my alternator regulator is bad and I need a new alternator because there should not be a backfeed. Is this napa trying to sell me a part or an legitimate fix? The alternator is old.

Mmm. Probably an honest mistake. But they are mistaken.

An '89 comes with a Delco SI (systems integrated) alternator. They will back-feed, as you found out. As I wrote above, the resistance wire will block back-feeding enough to kill the original type ignition. If you substitute something aftermarket, the resistance may not block back-feeding enough to kill the engine.