An engine accessory which generates alternating current (AC). The electricity is then fed through diodes which converts it from AC to direct current (DC), which is usable by the automobile in general. The alternator is usually driven by belts which are connected to the crankshaft of the engine which ...

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7
votes
2answers
74 views

Is any power from the alternator 'free'?

Cars generally (and specifically a Honda Accord 2002) are not very energy-efficient. Given all the inefficiencies, is it "free" to plug in, say, a smartphone into a car to charge while I am driving? ...
7
votes
4answers
2k views

How to assess battery charge level and alternator performance?

What diagnostics can be done to to assess battery charge level? I'm interested both in one-off tests like can be done in car service and also continuous monitoring during normal use. Car panels ...
7
votes
3answers
1k views

Does idle RPM increase when there is heavy load on the electrical system?

I am thinking about installing a 500w halogen (HDX brand) on the roll bar in my jeep as the dome light because often I work in the back when it is dark or when I would like more light. The 500w light ...
7
votes
2answers
2k views

Failing alternator, idler pulley, or something else?

I have 1997 Chevrolet Lumina sedan. I’m trying to diagnose a sound coming from my engine. It is a “whirring” noise that varies with the engine speed (e.g., if I accelerate, the sound becomes louder ...
5
votes
2answers
971 views

Can an engine stop from a bad battery?

The car is a 2005 Toyota Corolla CE. Its engine is the 1ZZ-FE, a 1.8L straight four that runs on gas, not diesel. The alternator is stock, and tests out just fine on the multimeter in both voltage ...
5
votes
2answers
245 views

How to detect a failing car alternator..?

Is there some way we can predict that the car alternator is about to fail in order to avoid a discharged battery situation on the road.. Although it will slow the sound of horn and will dim the ...
5
votes
3answers
211 views

93 Nissan Sentra SE-R, replaced alternator voltage still low

My car died while I was driving it, but I can put the battery on a charger (or from another car, with jumper cables) and get it running albeit for a short period of time. I put a multimeter on the ...
4
votes
4answers
11k views

How to diagnose a starter motor that does not work

My e46 M3 would not start when I got to the parking garage after work. When I first turned the key, I heard a sound like grinding gears, but I was so startled that I immediately stopped trying to ...
4
votes
1answer
940 views

How to repair alternator slip rings to stop squeaking?

Background I have a new Bosch CS-130 style alternator with a couple hundred miles on it. Since I installed it, it's been a little noisy, but I attributed that to the brushes breaking in to mate with ...
4
votes
1answer
60 views

DIY Alternator Belt Tensioner

I've got a diesel engine in my boat, but the previous owner had somehow snapped the alternator bracket, and fitted it fixed to the boat rather than the engine. Now the alternator doesn't move when the ...
4
votes
1answer
43 views

How long should fusible links be?

I've installed a 12" fusible link as a replacement for a fusible link on the line that charges the battery from the alternator. I showed the OEM part to the guy at the parts store and he gave me a 12" ...
3
votes
2answers
1k views

Noise in stereo that changes pitch with engine RPM

This is a question of curiosity. I have a '98 Acura Integra, a cheap car stereo with a 3.5mm aux in, a cheap inverter and a smart phone. If I have the smart phone audio hooked up to the car stereo and ...
3
votes
1answer
136 views

Battery light comes on after starting the car. How big of a problem is this?

On my way to work this morning, the battery light came on. I would say it was about 2-3 minutes after I started the car. My drive to work is only a 10 minutes drive, and the light was on the whole ...
3
votes
2answers
166 views

'03 Mazda Tribute needs jumped every time it starts

I have a 2003 Mazda Tribute. I'm not entirely sure what the problem is with the vehicle. I suppose it could be the alternator or just a dead battery, but could also be something more detailed. I have ...
3
votes
1answer
25 views

Battery dash light comes on when starting car then disappears while driving

2002 Honda Civic EX here. When I start my car, my battery dash light has been staying on usually until I get onto the highway, then it will turn off. If I hit a stop sign or red light, then it'll ...
3
votes
2answers
1k views

Why did my car stall when I used the foot brake?

Preface: I drive a 2004 Peugeot 206, manual On the motorway the other night, one of my tires blew out. I managed to pull over and change to the spare wheel in about 30 minutes (having never changed a ...
3
votes
2answers
655 views

What is the correct/factory wiring for a Suburban 1998 battery/alternator?

I have included a picture showing what I have now on this Suburban. Note that there is wiring not shown in the picture which is a second electrical connection to the positive side of the battery ...
2
votes
2answers
180 views

Safe resistance between alternator and battery?

I am trying to figure out which awg of wire I need to get for my new, 160 amp, alternator. I found this chart which shows the resistivity/length of different wire gauges. Chances are that I will not ...
2
votes
3answers
103 views

Effects of significant draw on alternator and battery

Hypothetically speaking, let's say I've equipped a vehicle with an aftermarket audio system with an amplifier that has a higher draw (in amps) than my alternator produces causing my average voltage ...
2
votes
2answers
473 views

Is alternator rating at pulley rpm or engine rpm?

I just got a new alternator for my jeep that says 160amps at 2k rpm. Is this rating for the pulley rpm on the alternator - or is it the rpm of the engine? Also, if the pulley is spinning slower than ...
2
votes
1answer
539 views

2004 Kia sedona intermittently wont start

my 2004 kia Sedona intermittently refuses to start. I have light, radio, electric windows but just doesn't turn over at all. If I leave it a few hours and go back to it, it'll start first time as if ...
2
votes
1answer
44 views

How to replace an alternator?

I've got an '05 Mazda 3 SP 2.3 and my question is how do I replace my alternator? My situation is pretty much the exact same as described on this site: ...
2
votes
2answers
48 views

Battery running flat on a regular basis

I drive a Vauxhall/Opel Astra Mk5 1.8l SRi, registered in 2004. For 2/3 months now I've been having to keep a spare battery in the car as the car battery is running flat. My first thought was that ...
2
votes
1answer
41 views

Specs for a Toyota Avalon 97 Alternator?

So I was told during a check-up at a Jiffy Lube oil change that their analysis turned up a failed alternator giving 12.1V. Given that Jiffy Lube doesn't replace parts and thus gains nothing if I do, I ...
1
vote
3answers
336 views

Is rebuilding an alternator a DIY project?

I'd like a high performance alternator similar to one of these. Is it possible to rebuild a stock alternator to similar output, using majority of tools one would have at a home garage? Of course one ...
1
vote
1answer
49 views

When is a magneto more efficient than an alternator?

A magneto is device similar to an alternator for creating electrical energy. Many small gas engines, including several road worthy motorcycles, use them to generate electrical energy. They can be ...
1
vote
2answers
2k views

Mustang charging system warning light on, but battery and alternator both passed testing?

I have a Mustang that the battery light stays on. I changed the battery and the alternator was checked by Autozone, they said it was good. I need help
1
vote
1answer
92 views

2001 Grand Cherokee Has not been starting?

In September someone broke into my car, nothing was missing but the alarm went off until the next day I came back from school and the battery was completely drained. So my dad jump started it and ...
1
vote
2answers
919 views

Rover 25 - My battery light starts flickering on/off on the dashboard

My girlfriend noticed this yesterday and thought it was odd, it stopped but started happening again this morning on my way to work, I think its a V plate.... "as I’m driving along my battery light ...
1
vote
1answer
14 views

Please advise on check gauges light on and battery gauge reads zero

Saw this thread while investigating what sounds like the same problem with my jeep. The check gauge light came on and my battery gauge bottomed out. But weird thing is, it ran fine. I drove it a few ...
1
vote
1answer
56 views

Juddering under load

My 2001 Ford Focus judders when idle, and is most seen under load. The rev counter goes from roughly 500rpm to 1500rpm during this juddering cycle, as if it is "hunting" for the correct place to be. ...
1
vote
1answer
511 views

97 Ford Explorer battery going dead

On Friday, my girlfriend's '97 Ford Explorer v6 lost electrical while driving. We were able to get it going again with a jump start. Lost electricity (lights / gauges) while driving, but were able to ...
1
vote
2answers
70 views

Battery dies frequently

I've had my 97 civic for a year now and the battery died about 3 months after I bought the car. Each time it died, I'd kick start it, drive for a few days, then it would die again. So I went to the ...