erratic voltimeter

[hurricaine]

Hey Guys,
Yes the beast is having problems again so here we go
While driving a crusing speed no problems noticed
while idling the needle on the voltimeter dipps way below 12 volts
with all accessories on at idle it dies will restart
while driving when ya hit the brake the needle dipps again and at night will make the lights blink dim then back for a second
bought the GM lifetime alternator parts/labor warranty the alt was just replaced took it back told them it was checked out the mech said it was puttin out the 115 amp/volt that it was correct
Read on the iceburg 170 self exciter what should I do?????? they will change to this 1 if I pay the diffrence between the 2

Thanks for all your help
"Caine

[dk05]

Have you checked the battery? Also, try taking off the battery cables and cleaning them with some elec. contact cleaner then reattach them. Could be bad wires also, maybe have them checked. That's the only suggestion I can give you if the alt is in good shape. Hope this helps.

~Dk

[93Oldsdroptop]

That is exactly what my 93 Cutlass alternator is doing and I know that it's on it's way out. It's whining also. If I put a voltmeter on it I can see that with everything on at idle it's losing voltage. My gauge is accurate as I have checked it out.

I don't know about those iceberg alternators. I take my alternators and starters to a little shop where the guy rebuilds them with better than OEM parts and have excellent results so far.

Good luck!
Peace

[Scott205]

It is also probably worse when the engine has been run awhile. The GM techs love to wait until they are ice cold and test them, the 91-93 are pretty notorius for starting to put out around 12volts a month or so before they go bad. then suddenly, bam.. they will die. usually leaving you stranded somewhere. Get it hot and drive it down to your GM place and show them on the volt meter (even one in the cigarette lighter) that it is putting out less than 13.3 volts..