Was wondering if this is right, I have been experiencing flat battery syndrome, went to disconnect the negative at the wingnut behind the tool kit and felt the cable to be hot to the touch, other than standard I am running an aftermarket sound system with a big amp.
'85 928S2 Euro

 

Chances are your ground strap is corroded underneath the plastic.

 

If only the Neg connection is hot, its probably a poor contact there. If both connections are hot, you have a major drain, or TWO poor contacts . If there is any sign of a spark when you reconnect either connection at the battery, when you think there should not be a drain, then you have a drain you should investigate. Whatever, clean the battery poles well (to SHINY!), grease (vaseline will work), reconnect. Do the same at the earth point on the body. If you have a meter with enough A range (10A), put that across the neg cable and the ground point, see what you get - normally should be measured in Milli amps - definitely under 50. If not, pull and replace fuses one at a time until you find the one that stops (or reduces) the drain.
jp 83 Euro S at 52k

 

Thanks guys

 

The grease doesn't affect the electrical contact? I would think that it would be fairly dielectric...

 

The grease gets squeezed out when you push the contact over the battery pole and clamp it. Then it stops/reduces corrosion caused by battery gases etc.
jp 83 S

 

Sexy. I'll keep that in mind...

 

Wally P from 928 Specalists has written up a yearly electrical maintenance schedule.

Visit their web site at: www.928gt.com and look under Wally's Technical Tips.

I would suggest that this electrical maintenance be carried out now and you will circumvent many electrical problem, such as you have described.

Tails 1990 928 S4 Auto

 

I have found the impregnated felt pads they sell at the FLAPS work well.

Somebody mentioned Vaseline - I prefer real grease b/c Vaseline has a low melting point and will quickly melt and run off a battery located in the engine compartment.