Engine RPM drops when Headlights are turned on
EG_Civic
03-01-2004, 10:04 PM
When I turn my headlights on, the idle drops probably 250 - 350 rpm. Is this normal? its not alot, I was just wondering if maybe the alternator is going bad. Any tips?
EDIT: I dont have a tach in the cluster, so Im guessing on the RPM, its probably closer to 100 RPM. Anyway, its enough to hear but it wont stall or anything.
EDIT: I dont have a tach in the cluster, so Im guessing on the RPM, its probably closer to 100 RPM. Anyway, its enough to hear but it wont stall or anything.
SilverY2KCivic
03-01-2004, 10:14 PM
Maybe have it checked out, but esp. on older cars, it's pretty normal as the headlights can and DO put a slight load on the car's electrical system, which inturn powers the car from the electricity that has to flow to the spark plugs to ignite the fuel.
Tomsriv
03-01-2004, 11:22 PM
100 rpm is normal. If it drops a lot it could be due to a weak battery (it acts as a voltage buffer) or a worn alternator.
EG_Civic
03-02-2004, 10:09 AM
Yeah, its closer to 100 rpm. If its normal, then I wont worry about it that much. Im gonna have to get a heavy duty battery/alternator anyway for my system.
88_SC_CRX_Si
03-03-2004, 10:08 AM
There is a slight lag before the Electronic Load Detector (ELD) sensor can signal the ECU. To increase the fuel injector pulse width, to compensate for the added load. It can take ut to 3 seconds in some cases....
88_SC_CRX_Si
03-04-2004, 11:25 AM
Might want to check the tension on the alt. belt, it could be slipping a tid-bit.
Just a thought...
Just a thought...
Ricochet
03-04-2004, 12:02 PM
It's normal as long as driving isn't effected..
SRV BOY
03-04-2004, 06:01 PM
Thats normal, my rpm drops when I use the power windows and sunroof, and I just put in an
ac delco heavy duty battery.
ac delco heavy duty battery.
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