When start my 98 3.0 and let it idle (to warm up), i look at the gauges and the radio and the lights are dimming. Does anyone elses do this?? They do it at about 1 second intervals. The revs fluctuate according to the dimming also. Dimmer, revs drop, brighter revs come up. No A.C. running no radio on. COuld my alternator be going out or is something more serious to blame. It doesnt hurt the cars performance, once i step on the gas it goes away. I honestly hope it is the alt so i have an excuse to put in my new pulleys. Thanks for your help and opinions

 

the dimming doesnt change ur idle, ur idle causes the dimming,

 

sounds like alternator problems, time for a new one and buy a 180 amp instead i had the same problem and then i got a new alt. and it fixed everything except my ground noise :angry:

 

so 30clstyle, are you saying that my idle is rough therefore causing the dimming (fluctuations in voltage because of rpm's)??? IM pretty sure its my alt, do i have to unbolt a motor mount and lift the motor a little to do the job (new alt)?? How much does a 180 amp alt run and where should i get it?? Thanks.