Amp gauge driving me nuts!!!
Thread Starter
Intermediate
Joined: Nov 2001
Posts: 35
Likes: 0
From: Colorado Springs CO
Amp gauge driving me nuts!!!
Occasionally while I am driving, I notice that my Amp gauge goes up into the red area. As I let off of the gas and start slowing down, the needle on the Amp gauge drops about 4 amps (all at once) and the GEN light will flash. The motor still runs fine and the battery is still being charged. It only does it occasionally. :mad
My question is...has anyone seen this before? If so, is it the gauge, the alternator or a voltage regulator or something like that?
Any help would be appreciated.
Thanks :cheers:
Bryan
My question is...has anyone seen this before? If so, is it the gauge, the alternator or a voltage regulator or something like that?
Any help would be appreciated.
Thanks :cheers:
Bryan
Racer
Joined: Feb 2002
Posts: 276
Likes: 1
From: Arlington Texas
Re: Amp gauge driving me nuts!!! (bryan78nCO)
Do you mean voltage or Amp gauge? I thought 78's had voltmeters, have you changed it? Regardless something seems amiss. Your Gen light should not be coming on.
Le Mans Master
Joined: Apr 2002
Posts: 7,281
Likes: 5
From: Boston
Re: Amp gauge driving me nuts!!! (Kingt)
I think that your Amp gauge is doing fine, the problem here seems to be the alternator.
Do your car has low amps when iddles? How about when its reved up little? This can be a lot of things. The amp gauge only shows you the amount of charge the your alt is charging your battery. Normally the amp should be close to "0" when driving and when you crank the engine it should go the the negative side while cranking, and right after the engine is runnig it should go to the positive side.
Hope I could help.
Paul
Do your car has low amps when iddles? How about when its reved up little? This can be a lot of things. The amp gauge only shows you the amount of charge the your alt is charging your battery. Normally the amp should be close to "0" when driving and when you crank the engine it should go the the negative side while cranking, and right after the engine is runnig it should go to the positive side.
Hope I could help.
Paul
Thread Starter
Intermediate
Joined: Nov 2001
Posts: 35
Likes: 0
From: Colorado Springs CO
Re: Amp gauge driving me nuts!!! (inferno-vette)
KingT:
You are right, it is a voltage gauge that show how much voltage the alternator is charging the battery.
inferno-vette:
Once it is started, even at idle, the voltage gauge shows about 13-15 volts (positive) charging, which is normal. On occasion, when I am driving, the volts will go up between 17-18 volts (which is in the red). The battery is fine and it seems to be good to go. When I start to slow down is when the voltmeter drops (all of a sudden) ot about 13-15 volts.
All the other time, it is right between 13-15 volts....where it normally is and has been for some time now.
Do you think my alternator is over charging the system on occasion?
By the way. My voltmeter starts at "0" and goes up to "18". It does not have the "0" in the middle and a negative on the left and a positive on the right.
You are right, it is a voltage gauge that show how much voltage the alternator is charging the battery.
inferno-vette:
Once it is started, even at idle, the voltage gauge shows about 13-15 volts (positive) charging, which is normal. On occasion, when I am driving, the volts will go up between 17-18 volts (which is in the red). The battery is fine and it seems to be good to go. When I start to slow down is when the voltmeter drops (all of a sudden) ot about 13-15 volts.
All the other time, it is right between 13-15 volts....where it normally is and has been for some time now.
Do you think my alternator is over charging the system on occasion?
By the way. My voltmeter starts at "0" and goes up to "18". It does not have the "0" in the middle and a negative on the left and a positive on the right.
Racer
Joined: Feb 2002
Posts: 276
Likes: 1
From: Arlington Texas
Re: Amp gauge driving me nuts!!! (bryan78nCO)
Bryan: As I'm sure you realize, there is a big difference between a voltmeter and an ammeter. Regardless, both are used as an indication of the state of the charging system. The ammeter measures current flow; the voltmeter measures system voltage. To maintain a good charge the minimum voltage (while running) must be above 13VDC. If yours is going as high as 18VDC, the regulator is sensing a high demand and asking the alternator for more output. Since the system is producing 18 volts the alternator should be OK. My guess is the regulator is defective. Are you running any high power demand add ons such as a high power stereo amp?
Burning Brakes
Joined: Mar 2002
Posts: 803
Likes: 0
From: South San Francisco CA
Re: Amp gauge driving me nuts!!! (bryan78nCO)
A good rule of thumb is "gauges don't lie". This isn't always the case, but when your gas gauge says you're out of gas, it's probably not the gauge that's the problem. Your amp gauge may well be reporting exactly what's going on with your electrical system. I would bet it's not the gauge...but some sort of short of something going on with the wiring. I had a similar problem and it turned out to be some worn through wiring where the wires go through the firewall. While driving along...the amp gauge would show a minus...not a plus. The battery was being discharged...and then I would hit a bump....or even for no reason....the needle would bounce back into the plus section. The problem.....wasn't......the gauge.
Instructor
Joined: Sep 2001
Posts: 171
Likes: 1
From: Rolla MO
Re: Amp gauge driving me nuts!!! (bryan78nCO)
If your battery is seriously overcharging, a couple of symptoms can be that:
1. You can hear the battery water "bubbling" excessively;
2. You need to add water frequently (if not a maintenance-free battery).
If it is overcharging, as stated before, it's probably your regulator - and you should
fix it.
1. You can hear the battery water "bubbling" excessively;
2. You need to add water frequently (if not a maintenance-free battery).
If it is overcharging, as stated before, it's probably your regulator - and you should
fix it.
