No Start Issue

[bluemp301]

Alright so I did a little searching on the forum before asking a question.

My dad's 71 Challenger randomly died on him when he was driving it last weekend.
Just shut off as if he turned the key off so no warning sign of any issues before that.

I believe he threw a few parts at it such as the ECM, ballast resistor, and rotor. I believe he also swapped out the coil to verify his was good.

Anyhow his car is not getting any spark. It does crank and it is getting fuel. I was at his house briefly the other night as he did a quick half-butt check of power at the coil with a voltmeter (I believe there was power but I didn't pay attention to which wire(s) )but he's not much of an electrical guy so it was more checking for power than he was looking at voltage readings and what they need to be.

I read something about the bulkhead connector being a common culprit, I suppose this is the next item to look into?
Can anyone tell me if there is anything else to look for or double check?

I appreciate any guidance!

[DeathProofCuda]

Before looking for other culprits, I'd recommend that you go back and get confirmation on all the half-butted checks that you "believe" have been done up to this point.

Sounds like you have no spark but you don't mention whether or not this has been confirmed. 

What is your voltage at the battery side of the coil while cranking?

[bluemp301]

I forgot to add we did pull a spark plug wire and confirmed it was not getting spark.

I'll try to swing by tonight but it might be the weekend before I'm able to give a helping hand.

I do not recall which wire it was but I remember seeing ~12v on one of them with just key on and not cranking. (again, half butt and not a lot of time spent testing as there needs to be) but we'll have some testing to do when I make it over to his house.

Just trying to get an idea of things to check as I'm a fan of diagnosing and not loading up the parts cannon but I'm green when it comes to electrical.

[tparker]

Start at the plugs and work backwards. No spark at the plugs, check the distributer and coil. Then back from there.

How did it fail? Was it working fine then just stopped? Was there any problems before? How long ago did it run? Last year or yesterday?

[bluemp301]

Yeah it's been running and driving fine.
He was driving it last Saturday and it just died on him while he was out cruising as if he turned the key off.
Went to start it back up and it just kept cranking but wouldn't fire and had my brother trailer it home.

[DeathProofCuda]

71 would originally have been a points dizzy, but you mentioned an ECM so I am assuming the car has been converted to electronic ignition?

I don't have electronic ignition on my Cuda, but my understanding is that the more recent Mopar ignition boxes are the weak link in that system.  They fail often enough that most folks recommend carrying a spare in the glove box for when you inevitably get left on the side of the road.  Therefore, I'd recommend that you confirm that your dad actually checked that with a known good unit.

You mentioned swapping out the rotor.  Has he checked the reluctor gap?

If you have good voltage at the coil, then the bulkhead connector is not your issue.

[DeathProofCuda]

Here's a link to an old Mopar Action article about roadside troubleshooting that you might find useful.

https://staging.moparaction.com/2016/03/16/roadside/

[Cuda Cody]

Start at the plugs and work backwards. No spark at the plugs, check the distributer and coil.

  I would check the distributor.   It's happened to me just like what you described and it was the distributor.

[dodj]

This could really be all sorts of different things. I would start by checking every connector in the cct. Column connector, bulkhead connector, valve cover connector. Coil connections, ballast resistor. My personal guess would be you have a column connector problem. BUT, that's just a guess.
After the connections are verified, time to get out the voltmeter.

[bluemp301]

Yeah the car has been converted to electronic ignition. (Didn't realize that was a conversion, dad did though)

I appreciate all the insight and info! Sounds like we will be working on the car on Saturday. I will report back with our findings and hopefully have an answer to the problem!

[DeathProofCuda]

This could really be all sorts of different things. I would start by checking every connector in the cct. Column connector, bulkhead connector, valve cover connector. Coil connections, ballast resistor. My personal guess would be you have a column connector problem. BUT, that's just a guess.
After the connections are verified, time to get out the voltmeter.

Can't say that I agree with that philosophy.  First thing to do is to get out the voltmeter.  If you have at least 9.5 volts at the battery side of the coil while cranking then you can be pretty confident that those connections are fine and that your problems lies somewhere downstream (ECU or distributor).  If not, then move back upstream and check those connections.

Or, as tparker suggested, start at the plugs and work backwards.

Ballast resister will cause a "no run", not a "no start" issue.  The car will start when key is in the start position, and then die when the key switches back to the run position.

[Rich G.]

 I'd first take the cap off and crank it over and make sure the distributor is actually turning. Pick up in the distributor and gap should be checked also.

[DeathProofCuda]

Start at the plugs and work backwards. No spark at the plugs, check the distributer and coil.

  I would check the distributor.   It's happened to me just like what you described and it was the distributor.

@ Cuda Cody, in your case what was it about the distributor that pooped out?

[Cuda Cody]

Mine just stopped working.  Nothing more... just would not provide a spark anymore.

[Chryco Psycho]

if you disconnect the - coil wire the coil should throw a spark everytime it is disconnected with the key on in the run position if it does everything is working except the pick coil in the dist or the ECU , this is the fastest way to eliminate most of the system .
I agree with checking the gap between the pick up & reluctor inside the dist , it should be .008 , if it is wider it will cause problems
ECU is the next most likely problem , Mancini has blue ones for $12 & they work great , buy 2 & put one in the glove box !! 

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