coil or ignition box?

[ShelbyDogg]

Did you say something about the - coil with the black/yellow, tach wire, and ballast resistor?
What's with the ballast resistor part? For the Ballast res. One side goes to a double brown wire, the other end has a blue wire. both supply voltage to the coil, One during cranking the other while running.  Is your tach aftermarket or stock?

Rob

[MEK-Dangerfield]

I think we might be barking up the wrong tree here. If it was wired wrong, you would never get it running, or it would run badly all the time. I had a similar problem at cruising speed. No backfiring, just a random miss. It was my vacuum advance messing with me. Maybe that applies here?  Just disconnect the vacuum advance line once, and see what happens.

   Mike

[70challengerrt]

I was just saying where the wires on the coil were hooked up. The vacuum advace works I checked it. Today I have a new electronic ignition box coming, its the only ignition part that is no new. I will keep everybody posted what it is. Two of my buddies are mechanics and they are interested in what is wrong too.

[Bullitt-]

Best of luck

[MEK-Dangerfield]

I was just saying where the wires on the coil were hooked up. The vacuum advace works I checked it. Today I have a new electronic ignition box coming, its the only ignition part that is no new. I will keep everybody posted what it is. Two of my buddies are mechanics and they are interested in what is wrong too.

Sorry, my point earlier was that your vacuum advance might be working too well. I mean it might be advancing the timing too far and causing a miss. It can be adjusted if that is the case.

  Mike

[71383bee]

What is intial and total timing set at? 

The NEW mopar boxes are junk, especially the orange box.  A miss at higher RPM sounds more timing related to me.  Are you sure it's not detonation? 

I've heard of bad wires shorting out at higher rpms due to the heat expanding the ends of the broken wires apart too.  I would try a new coil and maybe a new box.  Use the LX-101 box from carquest versus the orange box they are much more reliable.

You could always us an FBO system too...

[70challengerrt]

Ok today I swapped out the electronic ignition box. Same problems. So I ran a wire from the battery to the positive side of the coil, it helped out alot. It doesn't start to stumble till about 4000-4500 now which can be carb. What voltage reading should I have on the 4 prongs of the ballist resistor?

[Bullitt-]

My service manual does not give a voltage reading All i've ever seen is  1-OHM resister. can you check? From the simple wiring diagram 12v to resister. Do you have a 2 post or 4 post resister?

[Bullitt-]

 I see  4 prong  I'll find my meter & check

[Bullitt-]

I have a digital meter & could not make heads or tails of the #s I saw flashing. Better defray to someone with prior knowledge in this area.

[Chryco Psycho]

12v on the twinned blue connectors , 8-9v on the coil feed & don`t worry about the green wire to the ECU , it doesn`t use it anyway

[Bullitt-]

  Hey 70challengerrt  did the ballast resistor ck out?  Those crazy readings I was getting made the wonder, So I bought a new one. Mine runs smoother now than in a long time. 

[70challengerrt]

This week I changed the ballist even thought the old one checked out fine. I had about 8 to 9 volts going into the ballist. I was checking to so why the voltage was so low and some where in the process of changing the ballist and checking the wiring when the voltage jumped up and stayed up ever since. Now the runs great and has good power. All we can figure is it was a bad connection from the wire harness and car sitting so long.Thanks for everyones help!

[Bullitt-]

  Goovy Man Groovy