92 vx new alternator voltage?
 

i got a cigarette lighter voltmeter and noticed my voltage fluctuates between 12 and 14? so i thought it might be something in the fuse panel to the cigarette lighter but i put a meter on battery and it matches what the voltmeter in cigarette lighter has. its a new alternator and was going to take it back to shop that installed it but just want to make sure it couldnt be something else causing it? does vx have resistor block? i found other civics have it but i couldnt find it for the vx? sounds like to me the regulator but what you guys think?

is the brushless alternator really necessary? i am not running one right now.

Depends on when you're seeing what.
If you're stopped waiting at a light, at idle, foot on the brake, blower on, headlights on, and such, I'll see 11s. If I'm over 2000rpm driving with no extra electrical load, coming off a cold start, I'll see 14.5. I think it's normal.
If you're parked just watching your voltage, no changes to engine speed or electrical loads, and your voltage is bouncing from 12-14v quickly, then I'd say there's a problem, likely w/ the alternator, or connections to alternator or battery

^THAT.

modern alternators do a pretty good job of keeping up, but they need some speed before they get near their peak outputs.

then you start getting into stuff like temperature compensated target charging voltage and clutched pulleys and other fun stuff and all conventional wisdom goes out the window.

ok just to clarify this is when its idling and warm with no load or driving and no load my voltage will change from 12 to 14 with nothing on but the radio.

so does anyone know what im referring to about the resistor block? does the vx have one?

do you have any other symptoms besides what your meters are reading? lights flickering or changing in intensity, gauges wiggling? what were the symptoms causing you to get the alternator replaced?

since you just had a shop put it on, you could just take it back and tell them what youre seeing. maybe they left something loose, or the new alternator has a junk diode. if its something they did, they should fix it. i'd be very leary about giving them any additional money though.

i have no idea on the resistor block

Clean the ground connections, especially the engine ground to the radiator support (wire from valve cover bolt to support metal). Voltage fluctuations like that are not normal. You can test the grounds with a volt meter. Start at the battery negative terminal and touch the other lead to various ground points with the engine running. If you detect a voltage, anything above a very small amount there is resistance in that ground connection which could be your problem.

regards
Mech

the alt was bad for sure but we had a foot of snow so i was at the mercy of the shop. i know the shop will take care of the alt no problem. i got no low dimming lights or gauge issues but i do have an engine miss i have been chasing since ive had it. and i was hoping it was related to when the volts goes to 12 but no change???

i replaced the ground cable on rad and trany. i will redo the grounds. hey call call on the volt check! i will try that! thks!

There might not be anything wrong. Honda uses alternators with two output levels and an electrical load detector. The ECU will reduce alternator output if there isn't much load on it. On my '91 Civic, any speed above 40 MPH should be 14 volts regardless of load. But I'm usually forcing the alternator into the low output mode. :)

i also have a 91 civic si and the cigarette lighter voltmeter stays around 14 all the time idling or driving.