recently my car has been experiencing some really annoying problems. First off my tach is all screwy, right now thats the least of it but it kinda goes in with the others. Lately my car seems to have an idle surge when there are not accessories/lights turned on, but when I turn them on the idle goes from surge to a LOW idle. Its not an all the time thing, every now and then it occurs. When the lights are on there is a noticable difference in brightness when at idle, when I rev they get brighter (headlamps and gauges). I think its the alternator but it has tested out fine. It wasnt acting up when tested though so it leaves me perplexed. Any help would be appreciated.

 

help, Im drowning here

 

ttt

 

Well you can either replace the alternator now or wait two months until it leaves you stranded on the highway...ps @ least keep your battery charged and that will prolong the life of your alternator.

 

Don't replace the alternator at all...

If the alternator is testing out fine, then how is your battery...

At idle, you car will use both the battery and alternator as a source for current... Test it out... With a voltemeter across both terminals, you should get 12.6v
A dying battery is not a good thing..

corroded battery connections as well as a bad battery ground are sometimes assicoated with this. Inspect and clean them.

fs