[mizhele]

hello ive got to wondering is this normal ??? ive got a 71 240z that runs great good idle no problems ( thanks to you guys here that helped me out with the car ) but i noticed the r.p.m.'s drop from a steady 800 at idle to a fluctuating 600 -700 r.p.m's when i turn the headlights on ??? is this indication of the alternator not pulling its full load or voltage regulator ??? or???? it really not too conserning since i rarly drive the car at night and once im under way the lights are full bright and work ok just wondering if this is somthing i should replace now before i get stranded or have no lights one day... thankyou michele have a great new years

 

[george71z]

When you get an answer, let me know! My 71 has lights that dim at idle and get brighter as the RPM's go past 1K. Fugeddabout the wipers. Rain-X is my saving grace. Some say it may be bad grounds. Or corroded connectors. Merry New Year to you to! Ooops, I forgot, this is America, we say HAPPY New Year! ( been watching 'Trading Places' too much)

 

[schmaydee]

...i'm not sure about a '71......i have an zxt82 ...i think the regulator is internal on it (not sure) but i dont guess it matters......when i first got my car i put black headlight covers on it...looked cool......couldnt see where the **** i was going though....so i (brainiac) figgurd i'd just get brighter lights (it already had halogens on it).....i got some (not legal for street) retina killer "off of the road" aftermarket headlamps....whew....(its a wonder i didnt melt the front end off of the car)....and ...yes!...i could see! (small aircraft @ long distances).....but they would just about drag my motor down enough to kill it....
.....to make a long story less long....it was my alternator....now they can check 'em while they are still on the car (for free) @ autozone or advanced (i believe)..if not, it aint that hard to get it (the alt) off and i know they can test it then...(for free).....might be worth it just in case you "have" to drive it @ night...(or turn on the heater)...and if its doin' that....somethings goin' out....if it developes a short it'll drain your bat..(i had to do "the fred flintsone"more than once before i broke down and got another alt) ..or if you have high resistance on the ground...it'll overwork everything in the charging sys...and something will screw up...could just be the bat goin' south and its demanding too much current (but it would do it "all" the time)..the +/- (ammeter) doesnt go "kinda wild" does it?
......i have an idle prob w/mine (@1k) but it stays right there when i turn on the lights (heater and everything else)....you could be losing hp (my gawd!) just when its charging your bat w/o headlamps .......does it do it w/the lamps off and the heater "blowing"?....that pulls more current that lamps......if it dont (doesnt), your charging sys is prbly o.k........and you have a bad ground (or the chassis ground or posts on the bat arent making a good connections) or loose connection in your lights (circuits).....maybe...
....s

 

[helowrench]

recently replaced the voltage regulator in my 82zx
remove alternator and disassemble .
the voltage regulator set me back a whole $10
it is soldered into the inside of the back case of the alt
have fun