Alternator problem?

[eXphoid]

I was driving my car today.. and it felt a little weird so I took things very lightly. At the traffic lights my fuel gauge would go from a full tank to less than half a tank and slowly move up again once I drove off.. I got to bunnings.. did my shopping.. 10 minutes later I come out to the car and.. it won't start at all.. I gathered it was my fuel pump so I tapped it a few times and tried starting... a slight progression but it failed after 3 chokes..

RACV come and jump starts my car. They say it's a stuffed alternator (which is less than a year old) claiming its not charging my battery enough to start my car.. mind you the car stalled once I got home and whilst i waited 30 minutes for RACV to came I listened to my iPod in my car audio and worked like i had a full battery...

Any ideas? It still won't start. I will try again tonight once its fully cooled down.

[v6lux]

Let's be 100 % clear on the fact your IPOD working is in no way any indication of the condition of your battery condition in the real world of cars! The current required for starting the car is 10 to 20 times that of your car audio system as with the current to keep your engine running when started!

Yes, your alternator brushes may be worn on the regulator or the alternator may be stuffed. Rememeber that reco alternators from an auto elec are not always new.

Trust the RACV guy and if you can get it off the engine, get it to an auto elec and have someone to look at the regulator, the brushes and even bench test the alternator!

[hako]

It could also be the cable at the back of the alternator giving problems...it goes hard and simply breaks off causing a no charge situation.
The easist way to ell if you have a flat battery is to put the headlights - if they are yellow the battery is flat....if white it's OK and the fault lies somewhere else. But in your case the battery is flat due to the alternator not charging so that will be first on the list to check as v6lux outlines.