When my car is on, all of my lights dim, inside light and outside lights. The get bright then dim and again and again. I just replaced the battery, what could this be?

 

Well..., you don't have one of those ginormous amps on that car powering your system??? And possibly a weak alternator or voltage regulator, or too low of an idle.

 

No, I have a little Rockford Fosgate for my door speakers, but even before this I had this problem. Ok, I will have my alternator checked, but can you help me locate the voltage regulator so I can replace it, and how do I fix the idle stuff?

 

Well it is most likely a internal regulated alternator. But I'm not certain when they came out.

 

Your 98, assuming it's the one in the pic, more than likely has an internal regulator, you need speical tools to open it and good luck finding a new regulator.

Best bet is to buy a new or remanafactored one. I suggest Advance Auto Parts (if there is one near you). I've also heard good things about O'Reillys but I don't have any of them near me.

I've gotten burned by too many "important" parts from Pep Boys and Auto Zone to trust them anymore

 

Put a volt meter right across the battery and see what the voltage is and what it drops to when the lights dim. If the voltage stays the same then reg is not the cause.
Report back what you find....

I assume the battery cable terminals are clean and tight...........

 

It's not "more than likely", this car has an internal regulator. It likely has a CS130 alternator. There is a TSB on these alternators. Corrosion builds up between the aluminum rear part of the alternator housing and the iron core for the stator windings, eventually causing the regulator to go bad. There needs to be a ground wire added from the rear of the alternator to the block. If this doesn't fix the problem, you may need a rebuilt alternator.

 

Advanced Auto PArts checked my alternator and found nothing wrong with it. So alternator is not it. And yes the battery terminal are clean and tight. I don't know what can be causing this.

 

Did you perform the test that Lady72 asked with the voltage check>>

 

Yeah, we kind of need more specific information to be able to give any suggestions...

- Eric

 

check the eng ground to the fire wall,and the small ground from battery to the rad support.remove alt belt and run eng does it still dim the lights.does the lights dim at a different rate with a change in eng speed.did you add the ground wire as joe suggested.

 

Try tightening the alt belt you should not be able to turn it by hand at all

 

subscribed. My lights flicker sometimes too.