All Lights Flicker

**vgm** · 12-11-2008, 09:41 AM

Recently I have been having a problem with my 98 SS. All lighta (headlights, tail lights parking odometer etc) are flickering. I load tested the battery and it came up bad so I got a new battery but that did not fix it. I tested the alternator and it passed with nothing wrong but i do have ac current into the battery. I was wondering if anyone else had this problem and fixed it. An help would be appreciaated. Thank you.

**shady milkman** · 12-11-2008, 10:21 AM

the tests dont tell the whole story...our alternators are severally under-powered...get either a 99+ truck alternator..i think its 180+amps and swap the plastic backing or go buy a aftermarket ls1 alt. that has higher amps.

**BlueMagicSS** · 12-11-2008, 11:34 AM

Do you have a stereo system or no?? I actually had a similar problem with the alternator, no stereo system. I replaced the alternator and it hasn't done it since.

**2001NBMZ28** · 12-11-2008, 11:55 AM

Is it continuous or only on cold starts? Could also be the air pump cycling.

**vgm** · 12-11-2008, 12:21 PM

No stereo system, aftermarket head unit and i replaced the two door speakers because they were blown along with all the other speakers in the car (they were when i got it) but those were all the stock ones. And its continuous happens non stop even if my headlights are off the odometer still does it.

**BlueMagicSS** · 12-11-2008, 12:24 PM

It could be that the alternator can't handle the load... did you have it load tested.... like I said I had the same problem...

**vgm** · 12-11-2008, 12:25 PM

Yeah i had it load tested it passed with no problems so im kind of afraid to throw an alternator at it before im positive.

**bigrondownhiller** · 12-11-2008, 01:28 PM

I would check all connections at the battery, starter and alternator. Look at all ground connections too. I think there is a fuse under the hood for all lighting. I would check and make sure there is no corrosion there either.

**vgm** · 12-11-2008, 05:46 PM

Okay i seemed tp have narrowed it down to being the alternator. Would someone be able tp tell me what the stock amperage is and if i should get a higher one or just go oem or if theres a upgraded oem?

**TransAm11973** · 12-11-2008, 06:02 PM

sounds like a bad ground to me if your alt isnt bad

**vgm** · 12-11-2008, 06:09 PM

Well i checked the grounds under the hood and main ground on the block and they were good. Could i be missing any?

**shady milkman** · 12-12-2008, 07:57 AM

Originally Posted by vgm

Okay i seemed tp have narrowed it down to being the alternator. Would someone be able tp tell me what the stock amperage is and if i should get a higher one or just go oem or if theres a upgraded oem?

i believe oem is 105ish ...look for powermaster ones..or like i said..get one from a 99+ truck...they will bolt right up and work like a charm as long as you swap the back plastic backings

**bigrondownhiller** · 12-12-2008, 08:34 AM

A stock alternator is fine if you dont have any extra accesories on the car.

**shady milkman** · 12-12-2008, 09:22 AM

Originally Posted by bigrondownhiller

A stock alternator is fine if you dont have any extra accesories on the car.

no it really isn't...there was a recent service bulletin talking about the amount of amps certain options and accessories pull..with all the options on my trans am....that is headlights,fog lamps, air pump, heater, fan...it left me with 5 amps to spare...and that is without the radio. now for your lt1...it is fine since your at i believe 145amps compared to ls1's 105amps.. late fourth gen f-bods need a 140+

**vgm** · 12-12-2008, 02:14 PM

Okay thanks guys il look into it and pick one up.

**BaddBird** · 12-21-2008, 02:35 PM

I have recently had this problem.Turned out to be the connection at the alt. The easy way to check is to unplug your alt and start the car and see if your lights still flicker.If they do your problem is somewhere else.

**BowTied** · 12-23-2008, 02:05 AM

I posted a test in another thread on alternator noise in the sound system. Again, hook up chargers and/or another car (jumped). You can isolate more surely to it being the alternator or its connections.

Also, was the alternator tested out of the car? If it was you are almost certainly talking about a connection being the problem.

But this could well be a combination problem, an alt getting old and a little tired and a connection that is getting more and more resistive. I hate to get to that point...but if you drive it long enough and it is a connection, you can feel the heat at the connector to blame!