Need electrical advice for an electrically-challenged guy

[lochenjons]

Hello! So this car has been a work in progress for quite some time. I bought it in 2018 and haven't had the space or time to do all the things I'd like to - such as clean up the engine bay and clean up the ratty wiring- but I did get the rusty trunk pan replaced, new rear end, all new disc brakes, new oil pan, fuel tank, etc, among other things to get it running, driving, and stopping reliably before we had our kid. My wife took it for a spin a few months ago and it shut off on the freeway, she was able to coast it to the offramp and into a parking lot. Luckily I was right behind her in the Yukon. We quickly determined that it was a no spark issue and went to the auto parts store and replaced the Coil, and Ballast on the firewall. We opened up the distributor cap and made sure all the contact points were clean, I even took some sand paper and cleaned them up a bit. Checked all the wires, and the ones going from the coil to the distributor but still no spark. This is where my electrical knowledge ends.

I have an electrical meter and that's about it. As far as I know all the electrical connections are intact and everything seems to be in place. I checked everything obvious by tracing wires and such back and forth. There's a couple butt splices I could replace since I'm not sure if they're good or not.

Is there any point in the system that's prone to failure or what would be a good place to start here? Would the best option be to repair the existing system or install something new in it's place? I don't know much so what would be a good system to install if I were to go that route?

Engine is a 383 - not the original motor that came with the car - and whoever put it in did some weird stuff.

Thanks!

 

[jimbosride]

Boy been there in my younger years.... I would start with the engine harness. Unplug it from the firewall, mark all ends then stretch it
out on the bench and see where you are. If it's in real bad shape consider replacing it with a factory OEM Repop.

There's allot of members here that can let you know what works and what does not.

 

[BeepBeepRR]

First off you said you have points. Secondly you have a electronic ignition box of the inner fender passenger side. Something seems weird. Im not sure if you can use an orange box with points. Someone will chime in with better knowledge. But here is a good place to start. Check out this diagram on the orange box and see if you have anything that matches.

Looking closer at your picture I see the electronic distributor wire connector just below the valve cover on the left. So it seems you have an electronic distributor. You could pickup a new ECU which is fairly cheap. Thats the orange box. @HALIFAXHOPS usually has some good used ones or new old stock ones for sale. But do check the wiring according to the diagram below instead of throwing money at the issue. Check this thread for his ECUs FOR SALE - ECU's

This is your picture I edited with a crayon and my 5 year old self.

 

[pnora]

I would make sure the distributor is turning. Then I would clean the ground at the ecu. Then with a meter or test light make sure there is power at the coil positive with the key on and while cranking.

 

[Geoff 2]

Agree, clean the area where the ECU box grounds to the fender. That grd connection is the return path for the heavy coil current. You have elec ign, not points.

 

[j-c-c-62]

How do we know it's not the timing chain?
The sudden stoppage when exiting interstate concerns me.
It is fairly easy to eliminate.
I had that happen to me once.
The LEO that stopped to inquire about my breakdown asked me if it was steam powered.
It made my wife laugh.

 

[Kern Dog]

First off, that sure is a mess of an engine bay! Holy cow, man...I would have addressed that before I drove it out on the road.
I see a GM alternator. You were not kidding, the prior owner sure did some weird stuff to that car.
If the distributor has two wires and a terminal like this on it, it is electronic. If it has one wire, it is a points distributor.

I always start by pulling one spark plug wire and putting a spark plug in it, then spin the engine with the starter. Look for some sort of spark from the spark plug. If you get nothing, back track to the coil wire. Pull that from the distributor and hold the end of the coil wire near the intake or something metal. Crank the engine with the starter....No spark? Take your test meter...Turn the ignition switch to RUN, that is halfway between lock and start. Test the coil at the positive terminal. It should have at least 8 volts. If it does, that means power is going into the coil but not coming out of it. If it gets no power, trace the wiring at the coil and go back from there. The way that spark module and wiring look, it could be a combination of things. I had the 4/5 pin plug at the module go bad to where it wouldn't maintain a good connection and I had to replace it. It looks like this:

Last summer, I had a sudden failure and had to tow my car home. Oddly, both the ballast resistor and ECM failed at the same time.

After replacing them, the car ran fine for several months, then the 4/5 pin terminal failed and I had to replace that.
For me, despite spending money in the right places and keeping my wiring tidy and in order, I still had some trouble. The no-spark issues are the only persistent issues that I've had with this car.

Are you ready for a real weird one? Random NO spark from a MP electronic ignition system despite numerous parts swapped around...

Good luck....try to learn from the mistakes of others....

 

[OneWheelPeel]

Besides what everyone said, if the rotor does turn and there is no spark I would check the continuity of each wire (I’m to talking about the spark plug wires), which you should be able to do on the car, as well an anything that you can unplug and hit with contact cleaner. That method has worked for me bunches of times most recently with a voltage regulator issue. Disconnect the battery when you do those checks.

 

[Geoff 2]

Another possibility is if the vac adv on the dist has been hooked up AND has high mileage on it, the p/up wire in the dist might be broken; because operation of the vac adv flexes the wires & they eventually break.

 

[Don Frelier]

There are a couple other potential points of failure that I didn't see mentioned here.

1, bulkhead connector ( big plug on the firewall)
2. Reluctor gap ( opening of the reluctor and pickup coil ) inside the distributor should be.006-.008"
3. Pickup coil itself

But you really really should get a new engine harness. Classic industries offers harnesses that come modified for electronic ignition.
But their website is pretty lousy to navigate.

 

[turbine68rt]

, bulkhead connector ( big plug on the firewall

Agreed

 

[Rockland71GTX]

Get yourself a service manual here:
Service Manuals – MyMopar

It looks like your car is a 70 or older so you'll also need a 72 or later manual with the electronic ignition wiring.
As mentioned before I would take the engine harness out and give it a good inspection and cleaning and then clean all connections on the bulkhead and ignition switch.

 

[HALIFAXHOPS]

Sounds like the ecu or pick up died on you to me. Troubleshoot them before throwing parts at them, the new ones suck also. In the for sale ads I have troubleshooting book if needed also.

FOR SALE - electronic ign Trouble shooting book

I have some copies of a great book for trouble shooting Mopar electronic ignition with a ohm meter. Askin $28shipped lower 48 Shoot me your e mail I will send a paypal invoice.

www.forbbodiesonly.com

 

[gkent]

How do we know it's not the timing chain?

He says he has no spark. Timing chain has diddly squat to do with spark !! I'm surprised someone who knows everything about everything doesn't know that !!!

 

[Jeff Peterson]

He says he has no spark. Timing chain has diddly squat to do with spark !! I'm surprised someone who knows everything about everything doesn't know that !!!

What if the chain broke

 

[Carcinogen]

Looks like you need to clean up after previous owner.

Trying to piecemeal what mess you currently have is going to drive you crazy.

The age of wire and hackery done to the wiring harness is enough to justify replacing it before it burns up possibly taking whole car with it.

 

[j-c-c-62]

He says he has no spark. Timing chain has diddly squat to do with spark !! I'm surprised someone who knows everything about everything doesn't know that !!!

A bit touchy, are we?

 

[lochenjons]

THANK YOU EVERYONE!

I can't tell you how helpful this information is. Once I get some free time (hopefully this weekend) I will devote some time to seeing if I can trouble shoot this.

To the guys remarking on how messy the engine bay is: I know... I know... My goal was just to get it running and driving. I have plans to rip the engine out and rebuild it properly at some point but that's probably going to be a job for my daughter and I a decade from now. My wife and I wanted to get the car to a point where we could drive it and enjoy it after replacing the big ticket items. It's on the list.


This weekend I'll disconnect the bulkhead connector from the firewall and stretch it out on my bench to make sure everything is good and clean as I go. If it's too far gone, I'll either fix what I can or buy a new one - don't have the $ right now to throw at this so hopefully I can fix it. Before re-install I'll clean all the ground contact points.

I'll verify distributor is spinning and test spark with a plug out once wiring harness is back in place.

Once again, thank you everyone. I'll let you know what happens.

 

[OneWheelPeel]

I'm in the same boat and have taken the same steps in just getting it drivable. I try to limit real downtime and make my projects drivable ones. I didn't pull my harness off the car to check it since it I go with the least disturbance approach.
Good luck, I'm kind of local, maybe one day we can compare ugly engine bays.

 

[RJRENTON]

First off you said you have points. Secondly you have a electronic ignition box of the inner fender passenger side. Something seems weird. Im not sure if you can use an orange box with points. Someone will chime in with better knowledge. But here is a good place to start. Check out this diagram on the orange box and see if you have anything that matches.

Looking closer at your picture I see the electronic distributor wire connector just below the valve cover on the left. So it seems you have an electronic distributor. You could pickup a new ECU which is fairly cheap. Thats the orange box. @HALIFAXHOPS usually has some good used ones or new old stock ones for sale. But do check the wiring according to the diagram below instead of throwing money at the issue. Check this thread for his ECUs FOR SALE - ECU's

View attachment 1792849 This is your picture I edited with a crayon and my 5 year old self.

View attachment 1792857

It looks as if the prior owner installed a GM 10 SI ALTERNATOR. Hopefully, it's field is connected correctly to the Mopar electronic voltage regulator. Most later model GM alternators used an internal voltage regulator and the field voltage is controlled via the internal voltage regulator. You appear to be using the Mopar EXTERNAL voltage regulator (the silver box to the right side of the ballast resistor)...and the jumble of wires behind the alternator are confusing and maybe connected incorrectly....may to contribute to your difficulties......just an additional thought.....and for what it is worth, it looks as if the car HAD factory A/C installed and the heater has been disconnected and the hose connections have been looped although not necessary because the when the thermostat is closed, the coolant is bypassed thru a cored hole in the water pump housing, below the thermostat. You are correct, the engine compartment needs straightened out......
BOB RENTON
BOB RENTON