Pulling my hair out.. Ignition. not starting

[451Mopar]

Is it easier to start with a cold engine, and hard to start with a hot engine?
My old truck had that problem (it was the bad battery cable.)
I converted almost all my old Mopars to CD Ignition boxes like the MSD6AL, or Crane HI-6.
They have been more reliable than the original style ECU, and don't use a ballast resistor.

 

[pedal2themetal]

Is it easier to start with a cold engine, and hard to start with a hot engine?
.

HI,
Yes but it doesn't matter if its cold or hot.. the last time it really didn't want to fire the motor was stone cold (it was first thing in the morning temp in the 30"s) yes the choke is working New Quick fuel.
I redid that extra ground wire to the ICU last night and I'll find out today as I drive it if it helped

Thanks take care, be safe
tim

 

[451Mopar]

If you search the site, you will fine all sorts of posts like this relating to the stock type electronic ignition.
I think that in general, the issue is the ECU having issues detecting the magnetic trigger from the distributor.
If you want to do some troubleshooting, use two different batteries. One just to crank the starter over, and the other to power the car like original.
What I was seeing on my truck, was the high current in the battery cables while cranking the starter was creating a small voltage drop across the cable, and when the key stopped cranking (Low current in the cables, so almost no voltage drop), the truck would want to fire, and that is why it was so hard to figure out when everything else checked out good?

 

[pedal2themetal]

HI All,
I cleaned and redid the ECU extra ground last night as suggested by 451Mopar. ,,, and so far today I've started it like 4 different times and drove it around and it started fine each time.. So I'm hopping that was the problem.. I'll know better as the week goes on.. Because as I said if it gets worked on it works for a while then starts acting up.. I'll see how it goes..
Thanks again take care be safe
tim

 

[YY1]

You're welcome.

 

[pedal2themetal]

You're welcome.

Yes thank you you mentioned that as well..
so far it has started all day..

take care be safe
tim

 

[Geoff 2]

Only start it once a week on THAT day, lol....

 

[pedal2themetal]

HI,
Well it was working fine.. then this morning on my way to my volunteer job it just quit. Just shut off. No bog like loss of fuel. so its an electric problem.. after a minute it started back up finished my drive to work.. On the way home it quit again sat a few minutes and it restarted.. So I'm thinking ECU or coil.. Ether way I took it to the shop. I hate electric problems.. The ECU and the Coil aren't that old
thanks
tim

 

[Don Frelier]

Sorry to say it but I'm not surprised.
Likely the ECU.
The only other thing could be the reluctor gap or bad pickup coil.
Coil would be at the bottom of the list.

 

[YY1]

Is your aux ground still in place on the ECU?

That's the first thing I'd have tried when the issue reappeared.

 

[pedal2themetal]

HI yes the extra ECU ground is in place .. first thing I checked.... Now I did see a Black wire (small) broken loose from somewhere but it is short and looks like it might have hooked to the starter relay, as that is where it is closes to.. Might me the stock ground for the ECU??

thanks
tim

 

[pedal2themetal]

Hi ok.. got the car back today.. mech said it was the rotor has a pin hole and was grounding out to the shaft when it got hot...
Not what I would have thought..
tim

 

[pedal2themetal]

WELL!! hELL!! HERE WE GO AGAIN!!!!!!!!!!!!!!!!
It only lasted 4 days.. 2 days ago I was driving 45 mph.. and it cuts out and dies but re-fires before I start stopping, and then today its back to not wanting to fire occasionally it turns over fine just don't fire ... OR it well fire just as I let go of the key .. (sounds like the ballast resistor don't it .. its been changed at least 2 times..)
I really didn't think it was the rotor and cap.... I'm am just about ready to DUMP THIS POS.... even after all the money I've sunk into it..

Fresh motor
front end work
front and rear seats re-done
new duel exhaust completely all the way out back
Plus all the shops throwing stuff at it..
new windshield
bits and pieces of chrome for when I get the body done
New dash cover..

If it gets F'ed with it works for a few days or a few weeks then right back to the same ol ****..
I don't know what it is.. stuff replaced some several times...in the pass 2 years by shops... and me..
Ignition switch 3 times
key tumblers 1 time
coil 1 time
ECU 2 times
Ballast resistor 2 or 3 times..

Seams the only thing that hasn't been replaced is the starter relay on firewall driver side.. Maybe that's it. not always sending the signal to the resistor to the coil? I might just change it for shits and giggles..
I've never had this kind or amount of trouble with a car.............

Help if you can..
Thanks take care be safe
tim

 

[YY1]

might be broken wire with good insulation.

That's a PITA.

How about the reluctor and the wire harness that connects it.

I've had a bad wire in that more than once.

 

[pedal2themetal]

Thank YY1
I'll check and see if I can test the reluctor ... I think that might be oem since 75 I don't remember changing that when I rebuilt it..
only has 74,000 miles on it but it is over 30 years old..

thanks take care be safe
tim

 

[LowBikeMike]

Got a soldering or tattoo gun? They can be used to trigger the electronic ignition as a way of load testing the system. Bad components will generally overheat and fail, also good way to have ignition working while you wiggle wires and see if it will fail?

 

[YY1]

The problem with testing an internally frayed or broken wire is that they often test good.

For the cost, I'd just replace the assembly, or possibly borrow a known good working distributor.

From experience, if I'm this far into it, I'd just replace that part

 

[pedal2themetal]

OK.. would I get some performance out of a better than stock distributor? motor is mildly built.. Performer intake, cleaned up exhaust ports and gasket matched stock heads.. cam is a 440 lift comp cam 20-210-2 I think.. with a 450 quick fuel carb. straight up timing set.
Car is my Daily driver.. when it runs... LOL..

Thanks take care be safe
tim

 

[Geoff 2]

Tim,
Hang in there mate. I think the problem has to be wiring/poor connection.
If the vac adv is working, then it pulls on the p/up coil in the dist & flexes the wires. Eventually the wire break..& you lose spark. So replace the p/up if old & set the reluctor gap to 6-8 thousandths & check the gap on a few teeth. If the teeth touch the pole piece, you get no spark.

 

[YY1]

See if someone on FxBO is selling a known working stock electronic distributor assembly.