Thread: Electrical Problem ??? Help Needed!

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Going nuts trying to figure out what went wrong... The engine has been running perfect. All of the sudden a few days ago The engine started to cut out as I was driving. It would cut out for just a second and then be fine after that. I didn't think much of it at the time. The car was fine the rest of the day. Then the next day I took the car out to test a new front stabilizer bar. The engine started normal and ran fine for the first few minutes then started to cut out again, worse this time. The car would start to cut out and stall, then it would come back to life. Luckily I was close to home because this time the condition did not go away. I figured maybe I have a loose conection or maybe a bad batch of gas.

Over the next two days I have been pulling what's left of my hair out trying to determine the problem. Here is what I have checked so far. Starting from the basics: The car is getting plenty of fuel and a generous spark. I checked the timing and that is dead on. I checked the compression, that is perfect as well. I got a fresh gallon of gas and ran off of that to see if it was bad fuel. Thinking that possibly the coil was going bad, I replaced it along with a new resistor.

The engine cranks fine and attempts to start and sometimes will run for a few seconds, but will shut right down. It definetly seems to me that I have some type of electrical issue. (maybe the ignition switch?)

What could cause a perfectly running engine to all of the sudden cease to function out of the blue. Especially when all the basics seem to be in place. Air, Fuel, Ignition...

Sounds simple right?

Any Ideas?

My setup is simple, nothing special: Stock 1973, 302 ford. Mallory Dual Point distibutor. Blaster 2 coil. Edelbrock aluminum intake and Edelbrock 1406, 600cfm carb.

I have seen this problem in another posting somewhere and it was the distributor. Do you have another one to try?

Try replacing the capacitor mounted on the outside of the distributor.

Sounds like a dist. problem to me.You are just going to have to go through it,keep us updated.Could be as simple as a new dist. cap.

make sure the fuel filter is not stopped up.

If it starts intermittantly not sparking on every cylinder, the coil is usually shot. from what you are describing though, I'm suspecting that you have a problem between the negative coil terminal and the plate where the points ground. Things to look for:
1) points that are burnt, pitted and bumpy indicating that they have stuck
2) check that dist shaft has no horizontal play, causing varying dwell
3)point and condensor wires that are internally broken and/or grounding... look carefully at all wire ends,even where they come out of the condenser... look for (arcing) burn marks. This goes for the wire that goes from the dist to the coil, as well. Where the electricity goes thru the side of the dist housing is vulnerable to grounding
4)Like somebody else said, change the condensers
5) I've seen ballast resistors that are intermittantly bad when they get hot. Eventually you'll know this problem by the fact that the engine will start but immediately stall when you release the starter switch. This symtom indicates that the full-time hot supply to the coil is broken and that the full-voltage bypass wire from the starter solenoid is solely supplying hots while cranking.

Your description of sudden intermittance doesn't sound like a fuel problem, but if you've got a transitional stall during acceleration, there are a couple of transitional fuel circuits in the design of all carburetors. Choke operation and pump shot can be easily checked visually.
If you know and have checked all these things great! I hope I've been helpful and not taken as condecending by discussing basic troubleshooting tactics. If you guys are way beyond me, I'll shut up and go to my room ;>

Try a new coil, they can develop an intermittent open circuit and act like that.

Do you have a aftermarket tach? If you do, try disconecting
at the distrib.

To check if its a switch problem or a resistor , run a wire directly from the positive side of the battery to the + side of the coil. Start the car as you normally would, (just be aware that you won't be able to shut it off without yanking that new wire).
If the car runs O.K., that narrows the problem down to bad switch or resistor.
Disconnect the resistor and run a jumper wire in its place (it won't hurt to do this for 15 minutes or so)----if the problem still occurs, then the switch is bad.

sounds similar to a problem I had with an HEI distributor.

My problem: the little tit on the pick-up coil which is supposed to orient the coil, had broken off ( somehow ). This caused the coil to move slightly back and forth. Eventually, the wires cracked... and would ground out intermittently.

I bet you have something similar. In fact, I bet if you dumped that ancient technology dual-point distributor in favor of a brand new HEI, your problems would dissapear.

I had a similar problem with an old mallory dual point I had when I first got my Camaro. It started sporatically missing terribly, sometimes cutting out and not running at all. At the time I was pretty inexperienced with engines, and I finally had to get it to a mechanic. He said it ended up being a little e-clip loose in the distributor gounding out the points plate.

an extra module is cheap insurance. I always carry one, and have never needed to use it. What's more, they install quicker than points, and you don't have to worry about setting the dwell. And we're talking about a DUAL point dist... naw, make the switch. the best thing about the dual points is the bragging rights. You'll never regret not having to set points...

hmmmm.....

Originally posted by firebird77clone
hmmmm.....

Don't worry about Denny firebird, he probably keeps an old mule around the house in case those points don't work. he quite smoking so now he don't have a way to set the points. What you gonna do now DW?

Originally posted by DennyW
Well, you certainly have a goodPOINT there.
My last name pertains to the mule also. I was teased a lot in the service. Wo-mac,

Wish I had caught that.