Sudden Loss Of Power

[Canadian1968]

The fact that it does it once and then doesn't do it for the rest of the trip is very odd. And hard to diagnose. Your just going to have to really pay attention next time it happens and see If there is anything you can find that is common that will help you figure it out.

Mechanical should be repeatable. Electrical can do all sorts of weird stuff. But since it's killing your ignition and maybe power supply you can narrow it down pretty quickly

 

[Geoff 2]

Usually if it is fuel related, you get some warning: engine runs rough, change in note, loss of power.

If it just suddenly dies, no warning, more likely to be electrical.

Is vac adv on the dist hooked up? If so. After a lot of mileage, the p/up wires inside the dist can break because operation of the VA unit flexes the wires. Disconnect p/up & test with ohmmeter for 150-600 ohms. Wiggle the wires while testing.

 

[Ray70Chrg]

Had the exact same problem about a year ago. Problem was the large connector under the steering column was slightly pulled on one end and that's where the Ign 2 wire connects, ty-wrapped both ends of the connector and have not had the problem since. Very scary when it happens because you lose p/s. Hope this helps.

 

[The Rebel]

Thanks a million l bet that's the issue!

Had the exact same problem about a year ago. Problem was the large connector under the steering column was slightly pulled on one end and that's where the Ign 2 wire connects, ty-wrapped both ends of the connector and have not had the problem since. Very scary when it happens because you lose p/s. Hope this helps.

 

[jwiley1811]

Lately I've had a weird sudden loss of power.

Car starts with no issues. Then about 15 mins later it just dies, so l restart with no issues after that. Happened yesterday while out on a drive so pulled off the road and restarted.

With the car running, l've played with the battery cables, engine harness, ballast resistor & engine ground and no loss of power, so I'm completely at a loss of what's going on.

Check the Alt. gauge . May need to replace or bypass

 

[The Rebel]

That should be ok as l had the gauges restored about 8 years ago.

Check the Alt. gauge . May need to replace or bypass

 

[RJRENTON]

That should be ok as l had the gauges restored about 8 years ago.

Quite possible, you're experiencing the "tired motor" syndrome, due to a multitude of problems ranging from:
. Corroded or loose bulkhead connections and associated wiring issues
. Bad coil, wrong coil, wrong value of ballast resistor, ECU going bad
. Vacuum leaks under the carb spacer
. Incorrect carb, be it Carter, Edelbrock-Carter, Holley or loose hold down hardware
. Including worn fuel pump push rod; fuel pump going bad
. Cam going bad
. Bad fuel....too high/low octane rating
. Initial timing including: vacuum advance connected to manifold vacuum source or ported vacuum source or not ar all
. The use of non-NGK spark plugs in anything
. Too much/not enough timing
. Use of 160° F thermostat
. Incorrect oil type
. Incorrect type and wax used
. And the inevitable Incorrect tyre valve stem cap torque
All of the above items can/will cause a sudden performance lack thereof.......just a few item's to consider........
BOB RENTON
.

 

[superbeedave]

I had the same problem last week for five days. I finally found the problem and it was high resistance on the negative side. It was at 1.5 ohm
when it is supposed to be under .5 ohm. Cleaned the battery negative cable where it runs to the intake and it was back down to .2 -.3. I ran it for 20
minutes and it never shut down at all.

 

[GiantRobo]

Gently shake the two prong connector wires from the distributor and wiggle the coil wires while idling. See if any changes in running or stalling.

+1 on this! Test the coil resistance and look for damage/leaking.

Had the same problem as OP. Car would just die while running. Turn off for a few minutes and it fires right up. Then dies again later, randomly.

Father in law and I assumed something with ignition. He offered me an MSD 6A system from an old hot rod project. Swapped it in and when l pulled the original, 45+ year coil, it had a dent underneath and was leaking oil.

After the MSD coil swap, zero problems for 25 years I owned it.