positive battery wire

[trucker677]

this morning I went to get my haircut, car started fine, drove fine, no issues, when I went to restart my car after my haircut the car rolled over fine and then stopped. I had no power whatsoever, no clock, no horn, no anything. I checked all of my fuses and they were good, I called the local towing place and they hooked up cables directly to the battery and still anything, Then we hooked it up to the boosting bolt in the front and it fired right upHas anyone had this problem before.

[harborman]

Did you clean the battery connections, both + and - ?? Also the ground strap at battery and at body connection in rear. Also the terminals at the "jumper" bolt you mentioned.

Many other ground points as well. There is a list here on this site some place. In and around engine compartment, by fuse panel, on top bell housing under the air cleaner, etc. Other problems result from bad connections on the 14 pin connector on right fender up front inside engine compartment. Under the car there is a big ground wire from engine to body on right side.

I would clean the jumper terminal first, disconnect battery, remove nut on terminal and clean all connections. Good luck!

[MPDano]

Your pretty much direct to everything when you jump up front. You probably got an issue with your Battery or the cables coming off the battery. How's the ground cable going to the body off the battery?

[trucker677]

when I first got the car last year it was a non runner and I did a sort of preventative maintenance and cleaned of the terminal and connections and the ground strap, the only one I didn't do was the booster bolt. What I found weird though was that I had no power to anywhere like my clock which runs 24 and 7. Thats where I am getting confused.

[harborman]

Originally Posted by trucker677

when I first got the car last year it was a non runner and I did a sort of preventative maintenance and cleaned of the terminal and connections and the ground strap, the only one I didn't do was the booster bolt. What I found weird though was that I had no power to anywhere like my clock which runs 24 and 7. Thats where I am getting confused.

Put a volt meter on the jumper bolt in front and see. At any rate, clean those connections at the jumper bolt. Remove wires and clean. Check the big cable from the battery to the front. Make sure your ground (flat cable) from battery to frame is good and connection to body is good. Make sure the cables are good. There have been problems with the flat ground cable going bad too. Did you clean ALL the grounds????? Especially the grounds on top the bell housing?? Just a matter of tracking it down and eliminating one at a time.

[harborman]

And finally......is the battery good??????

[anakilat]

I had a very similar problem. Intermittently the car would just die - no electrical at all. Tow it home and wait a day, it would be fine. It was the connection from the battery negative terminal to the rear ground. It looked clean and was very tight. I finally took it off and re-cleaned it. Haven't had the problem again for 8 months.

[trucker677]

thanks all for the tips, I will redo all the grounds and everything and see if it happens again.

[Landseer]

Do all grounds and positive connections throughout the car. There are threads about it.

Sometimes cleaning ends of ground strap works, however---

What happens in wet climate cars is that the moisture conducts up (either end) of the copper weave and corrodes beneath the plastic shroud. As electrons pass, heat builds and changes the resistance, and can cause the car to shut down or not start, when minutes ago it was fine.

So, for some of us, cleaning the ends is not enough. New ground strap is needed. At $60 each, I usually opt to substitute a $7 generic round cable first to be sure. And/or slit the cover off of the flat original strap looking for a whiteish grey strip that denotes bad conductivity.

Sometimes cleaning the ends can inadvertently flex the copper weave and give a few more miles.
Other times, just the ends need cleaning.

[trucker677]

Thanks for the info, very useful. I will look into it for sure.

[PC-85-928S]

Change ground cable

[tmpusfugit]

Flat ground cables are available from places like O'Reiley's Auto Parts, Tractor Supply, Sears Automotive, and NAPA stores. It is sometimes difficult to get precisely the same length as the 928 uses. I went with one that was 2" longer than the Porsche cable, it was not sheathed with a plastic sleeve. I got a large diameter shrink tubing that fit at Harbor Freight, put it on the cable, shrank it, and bingo, had a completly functional ground cable fo about $15....

[Pete R]

Originally Posted by harborman

And finally......is the battery good??????

+1 take out the battery and have it tested. Sounds like when my battery lost some cells. It would read 12v but some of the cells were dead so it had no amps to turn over the car.

[harborman]

Originally Posted by tmpusfugit

Flat ground cables are available from places like O'Reiley's Auto Parts, Tractor Supply, Sears Automotive, and NAPA stores. It is sometimes difficult to get precisely the same length as the 928 uses. I went with one that was 2" longer than the Porsche cable, it was not sheathed with a plastic sleeve. I got a large diameter shrink tubing that fit at Harbor Freight, put it on the cable, shrank it, and bingo, had a completly functional ground cable fo about $15....

Since it's the ground cable you probably did not have to shrink cover it. The original is not covered (on my car). Great on places to get a replacement, will keep that in mind if I ever need one.

[Mrmerlin]

Harbor FWIW you do want the ground strap to be covered otherwise disconnecting the end of the strap will not guarantee that the battery power is isolated from the car.
If your strap isnt covered then its not stock

[harborman]

Originally Posted by Mrmerlin

Harbor FWIW you do want the ground strap to be covered otherwise disconnecting the end of the strap will not guarantee that the battery power is isolated from the car.
If your strap isnt covered then its not stock

I understand what you mean on the covering but normally to be sure, you disconnect at the battery. That way there is no chance of connecting to the body. But I know we have the ground connection at the twist knob and stud in rear. A bit strange indeed. However the end could still hit the body and make contact inadvertently when disconnected. Yes, mine is covered.

[Danglerb]

Last time I looked I didn't find any that were long enough, looks like this hot rod place has some now (2 gauge 27").

The Hot Rod Company - Ground Strap HD - 27"

[Landseer]

May or may not be the OP's issue, BTW.

Anyway, here's a particulary lovely one from my 85 car --- no, they don't need to be this polluted to fail

[Mrmerlin]

Harbor the reason for the wingnut connections is so you dont have to remove the spare tire and any other things in the pare tire well. if the ground cable iosnt isolated the you could stil;l have a HOT system even though the wingnut is removed..
Also you should make a card board ground strap cover to fit the end of the strap, this will keep it from grounding to the chassis

[harborman]

Originally Posted by Mrmerlin

Harbor the reason for the wingnut connections is so you dont have to remove the spare tire and any other things in the pare tire well. if the ground cable iosnt isolated the you could stil;l have a HOT system even though the wingnut is removed..
Also you should make a card board ground strap cover to fit the end of the strap, this will keep it from grounding to the chassis

Hi Stan,

Yes I know why they did it. I guess normally one does not need to remove the ground unless changing the battery. It's a good idea as long as you know someone has not installed another ground from the battery, say for a car amp, 2-way radio or something. I guess you would know if you disconnected it and still had lights, etc. When disconnected I do cover the cable end with some insulating material so it won't make contact.

Wonder if Trucker677 has found his problem yet?