'68 Satellite 440 Shuts Off

[Buckeye440]

'68 Satellite, 440 Six Barrel. The issue that occasionally appears is when the headlights are on. The first time the engine shut off I was getting ready to leave the house at night, started the car, turned the markers on, pulled down the driveway, flipped the headlights on and it shuts off. I turn the headlights off to restart it, starts strong, everything SEEMS normal from then on. While driving I make a few stops at lights and corners, still fine. I pull up to a red light near the house, instantly shuts off as soon as the car comes to a stop. I turn the headlights off, starts strong again, turn headlights back on and I have to press the gas pedal just a tiny bit to keep the RPMs up. The first time it happened I thought maybe the battery was weak, it was, so I replaced it, and the issue is still present. Any ideas?? Thanks!!

 

[The Shoe]

Hey what ignition are you running? Points or ECU? Stock style alternator or 1 wire unit? And factory voltage regulator or no?

 

[Buckeye440]

Hey what ignition are you running? Points or ECU? Stock style alternator or 1 wire unit? And factory voltage regulator or no?

I have the Mopar chrome voltage regulator, multi-wire alternator, and MSD Blaster 2.

 

[The Shoe]

Does the car have its original wiring harnesses or updated wiring?

 

[Yatzee]

'68 Satellite, 440 Six Barrel. The issue that occasionally appears is when the headlights are on. The first time the engine shut off I was getting ready to leave the house at night, started the car, turned the markers on, pulled down the driveway, flipped the headlights on and it shuts off. I turn the headlights off to restart it, starts strong, everything SEEMS normal from then on. While driving I make a few stops at lights and corners, still fine. I pull up to a red light near the house, instantly shuts off as soon as the car comes to a stop. I turn the headlights off, starts strong again, turn headlights back on and I have to press the gas pedal just a tiny bit to keep the RPMs up. The first time it happened I thought maybe the battery was weak, it was, so I replaced it, and the issue is still present. Any ideas?? Thanks!!

Would it be safe to assume that during daylight hours, when the headlights are off this does not occur? If so, the simple and least expensive fix is to not drive at night. Just kidding. It would appear as if there is a severe voltage drop when the lights are turned on, and if occurs at idle or low rpm's then the alternator can not keep up. Probably the best way to deal with the situation would be to install a relay kit for the front lights that gets it's power (fused) directly from the battery which will act as a buffer to prevent voltage spikes and drops. Either that or revisit your charging system components and wiring and especially the alternator. I doubt anyone to give you a guarantied fast solution to the situation with out more investigation. You really need to know your voltage and amperage output from the alternator and weather your voltage regulator is working as it should.

 

[Yatzee]

Would it be safe to assume that during daylight hours, when the headlights are off this does not occur? If so, the simple and least expensive fix is to not drive at night. Just kidding. It would appear as if there is a severe voltage drop when the lights are turned on, and if occurs at idle or low rpm's then the alternator can not keep up. Probably the best way to deal with the situation would be to install a relay kit for the front lights that gets it's power (fused) directly from the battery which will act as a buffer to prevent voltage spikes and drops. Either that or revisit your charging system components and wiring and especially the alternator. I doubt anyone to give you a guarantied fast solution to the situation with out more investigation. You really need to know your voltage and amperage output from the alternator and weather your voltage regulator is working as it should.

 

[oldbee]

Easy stuff first? Check EVERY ground on the car!! Grd strap from block to firewall?

 

[PurpleBeeper]

I'm with oldbee on this one. It sounds like a ground issue. My 2nd guess is the voltage regulator is on its last leg.

 

[Buckeye440]

Does the car have its original wiring harnesses or updated wiring?

The wiring looks to be mostly all original.

Easy stuff first? Check EVERY ground on the car!! Grd strap from block to firewall?

I haven't checked yet. This, and the alternator and voltage regulator will be next on the list. Thanks

 

[The Shoe]

I agree, ground check and alternator output are easy first steps. Maybe try pulling the headlight switch on before you start, then turn them off once it's started to see if the rpm's increase?

 

[Buckeye440]

If so, the simple and least expensive fix is to not drive at night.

Believe me, that was an option of sorts haha

 

[Don Frelier]

Besides the other suggestions.
Try a voltmeter on the battery and at the ballast resistor on the wire to the ignition module.
See what happens to the voltage when you turn on the headlights or press the brake.
Check your spark with a spare plug from the distributor coil wire as well.
It starts OK?

 

[Buckeye440]

Besides the other suggestions.
Try a voltmeter on the battery and at the ballast resistor on the wire to the ignition module.
See what happens to the voltage when you turn on the headlights or press the brake.
Check your spark with a spare plug from the distributor coil wire as well.
It starts OK?

Battery is brand new and it starts strong... What do you mean by "from the coil wire" with a plug?

 

[Don Frelier]

Take a spare good spark plug connect to the coil wire where it goes into the distributor or use an extra plug wire if you have one.
Hold the plug on a good ground and have someone crank the engine (just a bit).
The spark should be blue or white and have a crisp sound. Should not be yellow.
This will gauge the health of your ignition module and coil. If it starts easily then it's probably good.

 

[PurpleBeeper]

Take a spare good spark plug connect to the coil wire where it goes into the distributor or use an extra plug wire if you have one.
Hold the plug on a good ground and have someone crank the engine (just a bit).
The spark should be blue or white and have a crisp sound. Should not be yellow.
This will gauge the health of your ignition module and coil. If it starts easily then it's probably good.

And do be sweaty and leaning against the car when you do this or you will get zapped. For a single cylinder, you can do the same thing with an extra plug in any one of the spark plug wires, grounded well, you not touching car & buddy cranking it over (a little)

 

[Dennis H]

Sorry to be all over the place, but I'm thinking dimmer switch or bulkhead connector. At least clean the connector if it has not been done recently. Good maint anyway. Gently, don't break anything.