RS battery meter

[Nick Dubya]

So, i had my alternator checked and battery checked and wiring checked and its all good

but for some reason when i come to a red light and idle for a long period of time (in gear), my battery meter fluctuates to the 13v line and then dies shortly after if i dont put it in neutral and keep it above 1000RPM.

my friend just helped almost the fix the problem because i had a vaccum hose leak, and there was a (supposed) vaccum hose that came off the throttle body that was just sitting there, so he just plugged it up.

it happens left often now, but the problem still persists

=Dubya

[wrightz28]

Belt tension.

[ikeyballz]

or slipping belt.. or something on the ACC line holding up the belt...? (i think my p.s does that.)

[Nick Dubya]

i suppose that could be a possibility. i talked to my friend about how i noticed that the oil pressure would drop to the white line before the redline when the car starts to have its trouble

he suggested using a thicker oil and checking the oil sending unit and maybe the MAP sensor for the vaccum problem

[droptop94]

Do you have stock pullys?
Or have you changed them?

[Nick Dubya]

they are the stock pulleys

[droptop94]

if you already had the charging system checked out and you have stock pullys then it does not sound like a charging problem.
sounds like you'r friend was on the right track with the vacume leak.
you may have other vacume lines that have leaks.
Or you may need a tune up.

[wrightz28]

keep it simple, a alternator is a belt driven accesory, if it is not being driven properly, it will not function properly. Check for the obvious first.

[Nick Dubya]

i have had the alternator checked multiple times over the last few months, and it's still good

[wrightz28]

The alternatro itself can be absolutely perfect, but it will not function properly on the car if the belt and tension is not proper.

What year is the car also?

[Nick Dubya]

thats true, i'll get the tension tested

it's a 1989 RS, TBI