86VetteBill

There's a parasitic drain on the battery and the "fiance @ the time" let the battery die a couple times. :mad Now that the car is under MY care, it won't be subjected to that anymore.

But that Diehard keeps coming back! After the car sits overnight and I turn on the ignition it says 11.1 volts. When I turn the key, it cranks very well, so I think I'm OK???

But, here's the question: I notice that the digi-dash tends to flicker - almost un-noticeably. But, when I use the turn signals it's more noticeable. :confused:

Next question has to do with the digi-dash connections, I suppose. I've got the 4+3 in the '86 Coupe and there's a shift indicator light. It's an illuminated 'up arrow' and a lighted message that says "UPSHIFT For Best Economy". Well, the "For Best Economy" light doesn't work WHILE DRIVING. But it DOES work when I first turn on the key and all of the dash lights start up.

Any thoughts??? :confused:

scorp508

The for best economy light does exactly as you described, this is correct functionality.

Also.... my digi dash would flicker when my alternator was shot. Replacing the alternator brought it back to life. :) So I assume an iffy battery could do the same.

You should be seeing more like 11.8-12.0 with the car off, 11.1 is reeeally pushing the limit.

86VetteBill

Thanks Scorp - I was thinking the same thing about the battery, even though it cranks like the devil. New alternator last Nov when the block was replaced. State Farm covered that too! :cool:

But, boy oh boy, I could swear that the "For Best Economy" light lit up b4 when it was 'time' to shift. Actually, the more I think about it, I'm sure of it. Why else would they have something like that just for start up and not for shifting suggestions?

9T3JIM

Definitely check your your battery terminals if you haven't already. I had the same problem in my 93, I pulled the alternator and had it bench tested, checked out ok. I went to check the battery, after disconnecting the negative terminal I put a wrench on the positive side and the cable and bolt fell right off. The disc on the positive terminal that the bolt screws into was completely rotted off. Put a new battery in started car and the flickering was gone.

jtjerry

check voltage at battery terminals with digital voltometer.
That in dash sometimes (bad connection, oxidation) display voltage lower about 0.5 to 1 volt.
If you have 11 volts at battery check the same when engine running. You should have after start 14.4 - 13.8 volts.
If less when check and clean all connection at battery, make sure that positive wire from alternator is in good condition (when in doubt give there second heavy wire from alternator to positive battery terminal). Check also how good is negative (ground).
I am do not sure, you may have bad alternator, but first before you replace alternator, digi dash, engine, transmission and finally all car :), simple check and make sure that voltage has good path from alternator to battery and to the ground too.
Jerry

86VetteBill

As I mentioned the alternator was replaced in Nov... I see the voltage you mentioned. I'm thinking that the battery doesn't have the 'staying power' that it should since the 'now wife' had killed it a couple times - drained it to nothing!

As far as the terminals go, the negative was replaced a couple months ago and I just re-tapped the positive, too! So, we're on the same page with things to check.

I'm still leaning towards the replace the battery theory...

Like I've eluded to before, the wife would love for me to sell it because she doesn't understand the fine art of tinkering!!!

DAC

Have Sears load test the battery. Should be free.