I have a 99 civic ex and for a couple of month now when the car is running down the highway or sitting at a stop light all the light kinda fluctuate dim and get brighter over and over again at a constant frequency... Is this due to a bad alternator or regulator, isnt these civics internally regulated with in the alternator? Help!

 

Usually those symptoms you explained would indicate a bad alternator.

 

If you have a multimeter (they are cheap) and take two readings.
Take a reading with the engine off. It should be at about 12V.

Take a reading with the engine on (all other electrical off). It should be about 14V.

This will also narrow down the problem if it's with the battery or alternator.

 

yeah and soon or later.the battery light will come on at your cluster...then time for a new alternator..bring it to local parts stores.they will test it for u at no charge