Dash flickering intermittent starting

[flamesoldier]

1972 challenger msd 6al, newer plugs, wires, distributor etc. the car has been doing something weird. You put the key in ignition and turn to go start and it sometime is dead as a door nail. Not even ability to turn over. No accessory of any kind and cabin light wont turn on when door open. Sometimes i will turn ignition on to run and all accessories turn on like radio etc but the dash and dome lights flicker. When attempting to start the volt gauge bounces and flickers along with light and sometimes i have spark and sometimes i dont. I was at first thinking something was wrong with my new msd 6al or my ignitin control module but then i thiugh if something was wrong with those it probably wouldnt fire up at all. When it does fire up intermittently there is jo problem and its perfect. I am thinking my ignition switch is malfunctioning or worn out needing replacement and contacts are shot what do you all think am i in the right thought?

 

[mrmopar340]

Check the big red wire coming up the steering coloumn. There is a connection of two sections of wire there. Unplug it and see if it's burned or shorting. It's a common problem on these cars.

 

[flamesoldier]

Check the big red wire coming up the steering coloumn. There is a connection of two sections of wire there. Unplug it and see if it's burned or shorting. It's a common problem on these cars.

Red wire on both sides clean and crisp

 

[Challenger RTA]

You have a volt gauge or amp gauge? that maters. The amp gauge always has power to it and to the alternator. Check the battery connections first, Fusible link then bulkhead connector also under column connectors. The next time it happens check what is mentioned in that order. Be familiar with all points so you can find it then. You might be correct ign sw going bad.

 

[flamesoldier]

You have a volt gauge or amp gauge? that maters. The amp gauge always has power to it and to the alternator. Check the battery connections first, Fusible link then bulkhead connector also under column connectors. The next time it happens check what is mentioned in that order. Be familiar with all points so you can find it then. You might be correct ign sw going bad.View attachment 124085

Alternator battery terminal matches battery output with multimeter and all connections and fuseable links are good and sound. There is no chance the neutral safety switch could be bad causing issue? Pretty much have it narrowed down to those two ignition switch or neutral safety switch

 

[Challenger RTA]

I short. The fuse box is powered up 2 different ways. Battery side is directly from fusible link through bulkhead connector. Batt terminal on fuse box always hot check there when you have the problem. The Acc side of the fuse box will become hot when ing sw is on. There again check. That is if it is wired as original. Also a 3rd power supply when car is running throught splice 1. Not relevant now.

 

[Challenger RTA]

The ign sw can be unplugged at the connector and jumped from the connector. That can be done the there it is low current draw there or from the starter relay.

 

[Challenger RTA]

I would have to say it is a power supply connection.

 

[flamesoldier]

I would have to say it is a power supply connection.

I bet you it is probably the starter relay or neutral saftey switch then, it turns over so something is blocking spark and the relay looks incredibly old worst case i will have a nice new one

 

[flamesoldier]

The ign sw can be unplugged at the connector and jumped from the connector. That can be done the there it is low current draw there or from the starter relay. View attachment 124087View attachment 124086

@challengerrta your the freaking man!!! It was a stuck starter relay i tapped on the case a few times and it must of freed the contact. On the way to get a new one

 

[flamesoldier]

Wellll i was wrong the relay didnt solve anything it was one of my random starts, i just put in a new neutral safety switch same no change. Im thinking its my ignition switch. When key is turned to run not start but run my volt meter trickles down then up and so does d/c gauge i check all connections and grounds everything if fine. multimeter check with everything was fine as well. Bulk head connections are good as well. When i turn the key to start my radio shuts off and gauges appear to bottom until the car starts, this makes me wander if the ignition switch is worn.

 

[Challenger RTA]

Look at the top diagram for start and run colors. Brown ing 1 start bypasses the resistor when starter is in gauged , dark blue ing 2 run. This is not how you have it wired now. But they have to be jumped. As I said unplug under the column use a jumper from battery red and feed run. Also from red touch to the start. that will by pass the ing sw. Try it a number of time and see if it works. You can use a house light sw if you want feed each one from the red. Leave it wired in and try the next day. Then you will know.

 

[Challenger RTA]

Don't forget about the battery motor ground and body ground in front of the battery.

 

[flamesoldier]

Don't forget about the battery motor ground and body ground in front of the battery.

So i found my flickering issue, my wiper motor was hot an making a funky noise, disconnected it from bulk head that solved that, i have power to msd 6a but no spark to coil and tested coil to be good so i think i found my intermittent spark problem.

 

[Challenger RTA]

With the plug under the column is plugged in. Use a test light to check for power. With the key in the run position see if there is power there. dark blue ing 1 start, With the turned to the start position check for power. Brown ing 2 run.

 

[flamesoldier]

The msd box has 12v but its not sending spark to coil so the box is shot it appears

 

[Challenger RTA]

I would think so. Not sure how you have it wired. If you have a factory ecm you could try it.

 

[Challenger RTA]

Is this how it is wired?

Make sure it is grounded.

 

[flamesoldier]

Is this how it is wired?View attachment 124104

There is no ballast resistor

 

[Challenger RTA]

That's what I was wondering. All I can do is keep shotguning you answers if I don't have the diagram. many of parts have gone by the way because of bad connection.