Had this happen on 3 occasions lately. Driving along and suddenly engine shuts off and no power. First time this happened I had a loose Positive battery cable. Fortunately I was able to pull the car over on to a safe shoulder. Tightened the cable and started right up. 2nd time this happened I was at a stoplight and couldn't get to the pass side to check the cable because of traffic. Cops stoped and help me get it to the shoulder. Lifted the hood and tried the cable. It seemed tight but I tightened the bolt again just to be sure. Started right up and off I went. A couple of miles further down the road it happened again. Repeated the procedure and made it home. Noticed the battery isn't secured and with our bumpy roads and a stock C2 suspension I was wondering if the battery moving around could cause the problem. It isn't able to move much but it can move a little. Each time this has happened I was able to tighten the clamp a bit and the car fired right up. Gonna try to install a hold down bar but wondered if it could be something else causing the problem.

 

Check the bolts on the other end. If the cables have the repair ends, I suggest you just get new cables. Red for positive and black for negative. You said "then engine just cut off and no power". Have you ever checked your fuse box connections on the engine side of the firewall? The "the red wire" syndrome may be causing your problem. Dennis

 

Search for threads about "Red Wire." I think there's a good chance you'll find the source of your trouble there.

And, yeah, secure that battery.

Live well,

SJW

 

Are you familiar with the "red wire syndrome" that plagues midyears of all stripes & sizes? There are plenty of horror stories & many varieties of "fixes" in CF archives; they should turn up abundantly with an advanced search in C2 forum, general category. Your symptoms on bumpy roads could be due to the inboard bulkhead wiring harness firewall connector making/breaking continuity of the top inboard conductor terminals. If you wiggle this multi-pin connector instead of fussing with the battery, you may isolate the problem. See photo below of circuit involved. Note the small red tape ID mark at the location in question. The conductor originates at the horn relay buss.

 

Next time this happens try the horn. If the car is stone dead but the horn blows the problem is in the firewall connector, left hand connector as you face it. Gently pull back the two ears being careful if its old. Pull the connector away and look at both ends for green corrosion and so forth. This is a very common problem and your description fits it to a T.

Dan

 

It won't be the battery. This connection feeds all power to the cabin. When it happens again, you'll find if you just wait a few OR slightly wiggle this bulkhead connector the car will work again for a while. If you pull that connector off and look, you'll most likely see it has been hot and is corroded. A SURE PERMANENT fix is to bypass that connection by connecting a new piece of wire (I prefer red) from the wire coming out of that connector to the back of the fuse box where the red wire connects, OR you can connect the other end of the new red wire to the connector on the headlight rollover circuit breaker with a ring terminal. Use the post on the circuit breaker that comes to the fuse box and not the one that goes to the rollover switch under the dash for the headlight motors.. This picture's plug is badly corroded, if yours looks to be in pretty good shape you may be able to just clean both sides of the connector and reconnect. If the red wire is the problem as said earlier (and your horn worked previously) it will still work. If you were losing connection at the battery, the horn also wouldn't work.

 

Thanks for the information. I will research it further. One thing I didn't mention is the positive post has a disconnect on it. The kind with the round **** on the terminal clamp. I was advised to replace this with a standard cable clamp which I'm going to do. Also when this happens I have no electrical power at all. Nothing works. Lights, horn etc and the ignition switch doesn't click either. As soon as I tighten the clamp it starts right up. I'll do the research and report back. Thanks again

 

There's a good possibility that you have corrosion where the screw **** threads are down inside that cut-off switch. Secondly, you would be better served to, simply, buy a new switch...they get old and tired. Thirdly, it's best to have the cut-off switch mounted on the negative battery terminal. Clean/tight electrical connections are key in all situations, especially both ends of your battery cables. Just some thoughts.

 

 

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The horn is the tip off. If the horn stops working and then starts working when you mess with the battery cable, then you’re in the right area.

 

This is Gold

 

Removed the cut off switch completely. Positive battery cable was a tad loose where it connects to the cut off. Put the clamp back on without the cut off and securely tightened it to the battery post. So far no problems. I hope I found the gremlin. Still with no emergency flashers I'm gonna get someone to follow me over some bumpy roads and see if it happens again. Keeping my fingers crossed.
Still have to fashion a custom battery hold down to keep it from bouncing around. Doing that tomorrow.
Thanks for all the advice.

 

You could also have an internal short inside the battery, doesn't often happen though.

 

Regardless of the type, battery disconnects only complicate an already weak connection for high amperage use. I have never had a failure like yours where the car dies while running, but have had plenty of cheap terminal clamps fail due to poor contact with the posts. I remember having to drive a screw driver between the clamp and the post to get enough power to start the car. Hoping you found your problem.

 

IMHO, this is the best battery disconnect. Throw that green **** crap in the trash can!

 

Time will tell I guess whether or not I got the Gremlin out by removing the cut off. Thanks again everyone.

 

Had the same thing happen to me but it was my 64 Corvair. I keep thinking it was a Positive wire problem but as it turned out bad negative ground

 

One of us should have weighed in by now, my apology. The cheap green **** quick disconnects sold at swap meets are a piece of **** if you will abide by my directness. Put it in your hands. Unscrew the **** and examine what is actually making a connection that is intended to pass 200 amps of starting current. Yours is likely all pitted and burned. If these go open under way they will play hell with your alternator.

Use a half inch wrench or a knife switch instead. The cheap green ***** are a well known problem.

Dan

 

thanks Dan, I did away with the green **** gremlin all together and now it rides in the trash. Don't really see the need for a battery cut off even if the car sits for awhile but this one was on the car when I bought it so I left well enough alone till the trouble started. There shouldn't be much if any drain on the battery sitting idle as the clock seems to be the only electrical component running with the engine off, but I keep a trickle charger on both this 64 and my 08 C6 just because.
The positive cable is connected directly to the battery terminal now as it should be and I fashioned a make shift hold down device to keep the battery in it's place till the correct one I ordered comes in. Hoping for no more issues with this problem. Now to figure why my dash lights don't work but that's for another post.