Sporadic engine cut off 69 Coronet

[Dennis H]

Eighty mile run yesterday, happened three times. As if ignition shut off. Total and complete, does not seem to be fuel as ithere is no stumble. Duration is up to 5 seconds, then back to life. Once at hot restart, turn key and nothing. Once at full warm up after some freeway romping. Once at idle standing still. Engine shut off for 5 seconds, then electric pump began running as I was outside the car. Running the headlights, AC, Dash Cam, Radar, and CD player. Alt and elecs have had some upgrades and seem to support all. There is no odor or blown fuses. I think it is ignition, the key has that funky loose feel but has for years. I cut down on the electric load, and took all keys off the fob (think GM) and it still happened. Gonna replace the ignition and examine drivers side firewall boxes. Any advice appreciated.

Car runs perfect otherwise. Going to Reno soon and don't want problems on the road with Linda along.

 

[Funship32]

Well here is what I can offer although is may or may not help since you added the line about the fuel pump running. If it is ignition I can say I've had a problem very similar to yours on my 89 Ram p/u. I would drive along and the engine would just stop w/o warning. Yet it would start right back up when I cranked it over. Ended up being the distributor cap believe it or not. However I've also heard of the distributor pickup being intemittently bad too...again this is depending on what kind of igition are you are running. But I had an 87 Chrysler where the pickup would crap out once the engine was hot.

 

[Dennis H]

Thanks. Pics attached. I will look there too.

 

[Hemi Rebel]

Check the bulkhead connector. Common point for intermittent loose connections

 

[bigmanjbmopar]

what ignition system are you running? are you still using the ballast resistor? Need more info

 

[Funship32]

Oooh...yeah that is a different setup than the OEM stuff so my pointers will probably be worthless. Sorry man. Good luck with the fix though...

 

[Dennis H]

OK, something may have gotten wet 2 weeks ago. Did some degreasing after a valve cover gasket issue. I am sure it is dry now as it is warm and dry as a bone here. Could a wet component have recurring symptoms after drying?

 

[Pops1967GTX]

Could the coil be overheating...intermittent coil problem?

http://www.msdignition.com/uploadedFiles/MSDIgnitioncom/Products/Ignitions/6420_instructions.pdf

 

[Dennis H]

To clarify, this is TOTAL electric shutdown including engine. Lights, radio, ignition, electric fuel pump, CD, everything. Like a kill switch. I have a marine-grade cut off at the battery, but it is clean and snug.

 

[benno440]

i can safely say it is an electrical problem lol

 

[Dennis H]

Just remembered, this did happen one time at start up. Car off. Turned key, nothing for a brief time. This points to ignition. Talk me through r and r of the ignition switch in a 69 Coronet R/T rallye dash. Looks like a lot of spaghetti up there.

 

[kiwigtx]

Your Ammeter on the dash maybe on the fritz. Check it out before you have an under-dash fire to put out unexpectedly.

 

[Dennis H]

Your Ammeter on the dash maybe on the fritz. Check it out before you have an under-dash fire to put out unexpectedly.

That has been disconnected for years. Got the Halon AND abc handy.

 

[bigmanjbmopar]

Fusable link at fire wall terminal, prob half fried bypass it, will look at wiring detail in a minute hard to type on an ipad sitting at a Bart station lol

- - - Updated - - -

I'm sure you have checked all the fuses. It would help if you tell us everything you have, I.e. Brands of parts etc. check for power at ignition switch check brown wire going out to ballast resistor.

 

[Dennis H]

 

[nm9stheham]

If it includes the lights it is most likely either the:
1) fusible link 'almost' blown and being erratic
2) the bulkhead connector where the fusible link goes in
3) the ammeter and its connections
4) the factory in-the-harness splice in harness behind the dash

A bad ignition switch will not cut off electricity to the lights, so that is not the issue for everything going dead.

Download the schematic for your car from mymopar.com...trace the large lead going through the firewall from the large terminal on the starter relay; that wire contains the fusible link. Work from there in through the firewall, to the ammeter, and then to the in-harness splice. Look for chafed and/or metled wires when examining the harness.

 

[bigmanjbmopar]

Dennis do you have a volt / Ohm meter? Do you know how to check continuity on a wire? I can walk you through it if not or you need help. Also here are the links to the wiring diagrams. Also just for the hell of it have you changed anything recently or within the last few trips out? radio, anything electrical?

http://www.mymopar.com/downloads/1969/69CoronetA.JPG


http://www.mymopar.com/downloads/1969/69CoronetB.JPG

 

[Dennis H]

nm9stheham and bigmanjbmopar I appreciate your time. Can't be sure about the lights, happened during light time hours. Did replace the electric fuel pump about 500 miles ago. jbc426 on Moparts is going to help me this weekend with this. I will follow the advice here. I will download the schematics and follow the 4 steps. Will,report back.

 

[nm9stheham]

Good luck runnin' this down....ya just gotta dig at it. Finding what is good is as important as finding what is bad. And I would advise you to go through the whole steps all the way into the harness splice, and then on to the ignition switch power feed and then onto the ballast and coil, even if it is just the fusible link for the immediate problem. This whoel battery to coil wiring and connections gets old and corroded and you can have multiple spots causing erratic ignition issues that plague you forever. It is tedious but, IMO, it beats body work! (I suck at that!)

 

[Dennis H]

Replaced the ignition a switch. Got a few miles and it shut off. When power is lost, the lights do go out. It stayed down long enough this time to tell. Now I have power and the starter won't spin like it is the switch - except it is new. Now there is power in the car between the normal detents on the ignition. Won't start. Can walk home from here, debating...