ignition help

72 charger with fresh build 340, engine will start when in start position but as soon as I release the key and is in run position I lose ignition. I tried ballast and ignition switch, keep backup ignition parts handy. still same problem, picked up msd coil tonight and gonna try in morning. Anything else I should be picking on or looking for?

Did you put the brown and blue wires together?

I'm assuming you are running a MSD box? What Crackedback said, that box and the coil need to be fed in ign1 (run) and in ign2 (cranking) & actually the OE system needs to be also and that ain't being done the way you have it wired right now (your coil & box are OK) tho you might benefit slightly from going to the MSD coil and there might be a longevity bennie related to MSD box/using OE coil combo (I ain't sure on that). Short version: post what system you have and how you have it wired & if you have that correct then with your VOM see if everything is being fed with the key "on" cuz that is when it is going dead

I have the OE elec ignition system, it was running until the starter burned up. Changed the starter and pulled off the carb to clean up, went to crank it back up and this is where I am. I was running a cheap bwd coil but just picked up a msd blaster 2 coil to install.

Alright, it starts then dies when you release the key. turn the key "on" & go under the hood with your VOM see if the ECU and coil are being fed. If not then pull/seperate the bulkhead & check there & either work upstream or downstream in that blue wire ign1 circuit for the open. www.mymopar.com will have the colors for you. EDIT this is the OE 4 terminal "dual" ballast/5 terminal ECU system right now?

yes, OE 4 terminal dual ballast/5 terminal ECU system

The wires are backwords

You've lost power to the IGN1 circuit (blue wire). Check the firewall disconnect for faulty connections.

found the issue, blue wire at the bulkhead making poor connection. Now if I can just get the fuel pump to actually pump fuel! Runs awesome when I fill bowl with fuel until it runs out! If it aint one thing....

Mech pump? if so, hook a 5/16 neoprene hose to the inlet nipple & run it into a nearby can of gas then prime the bowls & see what develops. this'll take the line rearward of the pump and the pickup/sock (all) out of the equation. Sometimes very worn pumps have a hard time pumping when being activated slowly with a slow cranking eng & you'll see the effect of that when a car has sit long enough to evap the bowls but with you priming the bowls that ain't an issue. the pump might be totally shot (whats the history on it) and do a good visual on the hard lines and the (2) short neoprene connector pieces (1) up front at pump inlet and (1) at the tank sending unit. I had a '83 Cordoba and the pump outlet nipple pointed to the horizontle line along the frame going rearward (no gas!) took a bit to figure that one out. it used a U shaped piece of hard line to route em right.

its a new pump and I already tried a line in a gas can, very little suction coming form hose when cranking. I put it up to my cheek and can barely feel any suction. gonna pull off pump and investigate some more this w/e

You've filled the bowls/inlet hose in a gas can/fired it up? if so does it keep running or die from the bowls going empty?

It runs great until bowl goes empty, very weak suction at hose in can.

Pretty much just sounds like the pump is bad. A parts house "airtex" is a pretty cheap pump unless you are needing more capacity than that.

second new pump on there that did this

I'd pull the pump & crank it & see if I could see in there to check out the cam eccentric