idle drops with lights

my idle drops alot when i turn on my headlights (h.i.d’s) or even if i turn on my fog lights, why would it do this, the lights should draw off the battery, not take power from the alternator correct? anyway to fix this??

have the battery tested, load tested etc. the alternater constantly keeps the battery charged…so you are right it isnt off the alternater but the alternater does have to work harder cause the battery isnt doing the job itself anymore…possibly

well i just replaced the battery, it did the same thing with the old battery as it is now, so im assuming its not the battery, and how do i test the load??

Voltage regulator

Say what?

OK class, listen up…

The cars batt. has one job, it is to supply power for starter motor and cars ign. system, [including fuel pump] once the engine has started all current, [power] the car needs should come from the cars alt., if the alt. can not supply enough current, either because it is old or you add more load, [HIDs] or a combination of both, you will need to upgrade the alt. to at least 110% of stock.

With that said, before I do anything else I would check all power and ground connections starting with the main grounds, batt. clamp and post, the chassis ground under the batt. and the engine ground, all should be removed, both contact surfaces cleaned to bare metal and reconnected snugly, there is also the valve cover to rad support ground.

Once done, see if it makes a diff., it should.

Now do the same with the pos.(+) side, batt. clamp and post, batt. to starter motor and batt. to engine bay fuse box, don’t forget the alt. to engine bay fuse box connections, [charge line] also make sure the main fuses are screwed down tightly.

Now go and have the cars charging system and batt. tested, “load tested”, most batt. and alt. shops will do this for free, it only takes a few min., this will tell you the condition of the alt. and the batt., [charging system].

Without doing the power and grounds the load test is really meaningless as it would only tell you what you already know, you have a problem, so you would have to check the wiring, [power and ground connections] to eliminate them as the problem then do another load test, once the wiring connections can’t be the problem the load test will tell you what is wrong and you can fix it.

It is a good bet the alt. is on it’s way west and replacing it will solve the problem, but doing the power and ground connections first is a lot cheaper, and if it turns out that it was a power or ground connection problem, you haven’t spent any money.

Question…
Did you replace the batt. because of this problem or was that a diff. issue? 94

[QUOTE=fcm;2066724]Say what?

OK class, listen up…

The cars batt. has one job, it is to supply power for starter motor and cars ign. system, [including fuel pump] once the engine has started all current, [power] the car needs should come from the cars alt., if the alt. can not supply enough current, either because it is old or you add more load, [HIDs] or a combination of both, you will need to upgrade the alt. to at least 110% of stock.

With that said, before I do anything else I would check all power and ground connections starting with the main grounds, batt. clamp and post, the chassis ground under the batt. and the engine ground, all should be removed, both contact surfaces cleaned to bare metal and reconnected snugly, there is also the valve cover to rad support ground.

Once done, see if it makes a diff., it should.

Now do the same with the pos.(+) side, batt. clamp and post, batt. to starter motor and batt. to engine bay fuse box, don’t forget the alt. to engine bay fuse box connections, [charge line] also make sure the main fuses are screwed down tightly.

Now go and have the cars charging system and batt. tested, “load tested”, most batt. and alt. shops will do this for free, it only takes a few min., this will tell you the condition of the alt. and the batt., [charging system].

Without doing the power and grounds the load test is really meaningless as it would only tell you what you already know, you have a problem, so you would have to check the wiring, [power and ground connections] to eliminate them as the problem then do another load test, once the wiring connections can’t be the problem the load test will tell you what is wrong and you can fix it.

It is a good bet the alt. is on it’s way west and replacing it will solve the problem, but doing the power and ground connections first is a lot cheaper, and if it turns out that it was a power or ground connection problem, you haven’t spent any money.

Question…
Did you replace the batt. because of this problem or was that a diff. issue? 94[/QUOTE]

i replaced the battery because i got a optima red top for a good price…