1CAMWNDR

iTrader: (21)

For some reason my Headlights and Fog lights pulse when the engine is running. Anyone had this also? Alternator going bad?? I just replaced the battery if that matters.

BigBadWolf

Sounds like a bad rectifier in the alternator. A problem I am currently suffering from although right now it's minor.

So... yea, sounds like it's getting time for a new one for both of us.

prince xizor

iTrader: (2)

From my research, there are a lot of people that have that problem. I seem to sense mine pulsate when I start to brake. The dealer said that was a normal occurance with the f-bodies. Maybe he was just feeding me a line.

Country Boy

iTrader: (24)

Mine used to do it and my GFs does it. I fixed mine by blowing up my motor and letting the alt. sit on the shelf for 16 months.

Its usually from a bad voltage regulator which = new alt.

1CAMWNDR

iTrader: (21)

I noticed the radio display doing it also. Mine is also worse when I brake.
Damn. Time to start thinking about an alternator.

SteelBallz

My lights always flicker when I first start up the car, the fog lights seem to be the most noticable. My interior lights do it a little too. I thought that it would be the ground for the battery. I have cleaned all of my grounds to my battery and it does not really help. My voltmeter doesn't move at all.

Don't worry about it, my dad's '01 Corvette does it too, and so does my uncle's '03 Z06 so it seems that it is normal...

ACW

Does replacing it with a higher-quality aftermarket alternator stop the flickering?

1CAMWNDR

iTrader: (21)

Yes, this is what I want to know also.
TTT.

1998TA__1991RS

iTrader: (23)

mine does it also BAD but my car eats up alternators for some reason (AC compressors too) im on my 5th alt. and 7th compressor, looks like its time for number 6

Demonicbird00

iTrader: (17)

mine does it only on start up then goes away after its warmed up

RhinoTA

iTrader: (1)

I just recently had the same problem, headlights flickering, especially with stereo on, (aftermarket amp etc). Dash lights would flicker after a while, and when i would hit the brake pedal it would dim lights.

Bad voltage regulator...which is inside the alternator.

Changed alternator to 145 amp, and put in new battery, biggest i could get. Problem solved. Still has some very slight dimming when the brake lights come on, only when i have accessories running, like lights, stereo, heater, and rear defrost.

1CAMWNDR

iTrader: (21)

Where did you get the 145 amp alternator, and how much did it cost?

RhinoTA

iTrader: (1)

I had this local shop do it here in illinois, ill find out where they got the alternator from, but it was about $225.

black00TA

iTrader: (3)

if your lights are dimming when you hit the breaks and when your revs drop it could also be a tensioner problem. often overlooked.

1CAMWNDR

iTrader: (21)

Hhhmmmmmmm. Maybe I will throw that on first just to have it out of the way. Might get lucky.

1CAMWNDR

iTrader: (21)

Will one of the 6.0L truck alternators (140amp) bolt right onto the bracket of an F-body?? A new 140 amp Duralast from Autozone is $159 + core. That's only $10 more than the 102 amp F-body alternator.

01ArcticSS

iTrader: (1)

My lights were all flickering, and eventually the RPMs would drop suddenly and the car would almost die (this is slow speed, stop and go traffice in Houston, mind you - it was fine cruising along between the stoplights)

Took it in under the GM Certified Used Car warranty and they replaced the alternator and one connector - the service rep mentioned something about the connector causing the alternator to go bad - maybe a TSB on this somewhere?

Anyway, mine is fixed. Good luck with yours.

Todd

Monello

iTrader: (1)

!! Good idea, i may go to autozone and compare the 2. Someone needs to look into this also!

abadss

iTrader: (4)

mine will do this on cold mornings or nights when i get it out. while letting it warm up i notice the lights flickering slightly, but once its warmed up it goes away. so we should check the volts coming from the alt? i'll look at it, but i am not so sure its not a battery problem either.

myk02k

I had the SAME problem with my car when I bought it just 2 months ago. The alternator needed to be replaced, but it wasn't as bad as draining my battery; it flickered my lights when I drove for a while and blew a few tail lights. If you have some type of warranty make sure you tell the mechanics to check the alternator when it's hot, they originally told me it was fine because they checked it with the engine just turned on. If it gets worse, you will have serious electrical problems, and your new battery will be shot.