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flyromeo3
04-28-2009, 06:59 PM
recently, ive noticed that my battery voltage meter has been acting strange lately. Needle moves between 14,-12. When I come to a stop while idling the meter will lower down to near 12 and upon accelerating it'll jump back up to near 14. Thats with my a/c , radio, headlights, fog lights on. Car doesnt stall or anything.

if I turn off a/c it doesnt really move down to 12. Kinda stays around 13.5-14


Sign that alternator is going?

I hear bosch and valeo are one of the ones i may have that differ in mounting brackets?

mwebb
04-28-2009, 07:16 PM
alternator

audi til I die
04-28-2009, 07:19 PM
Sounds like your alternator is faulty, but my alternator in my A6 did that for 2 years and still hasn't failed so it may just be a screwy one. What I did to figure out wether mine was Valeo or Bosch was I took a flashlight and mirror around the alt until I found the engraving. Better than taking out the unit and putting it back on til it goes

flyromeo3
04-28-2009, 07:36 PM
How can i remove the serp belt so i can swap it out?

99 2.8

audi til I die
04-28-2009, 08:02 PM
How can i remove the serp belt so i can swap it out?

99 2.8


Correct me if I'm wrong but don't you just gotta pull a little bit to release tension and just unhook it from the pulleys??? Been a while since I've done this. Maybe you gotta relieve stress from the tensioner. Yeah... I think that's it, untighten the tensioner from under the car I think.

flyromeo3
04-29-2009, 05:24 AM
would needing to replace your serp. belt cause these symptoms?
I found my repair manual and seems very easy to replace. I'm just hoping theres clearance so I can fish the belt around the fan.

I figure i'll replace the belt first. If symptoms still there I'll buy an alternator and replace it myself without removing the front.

audi til I die
04-29-2009, 07:30 AM
well you'll need to put a new serpentine belt either way so go ahead and try that. But the only reason I'd think a belt would slip is if your pulleys arent aligned and the belt has worn uneven. Ever had any pulley (alt, ps, etc) changed? How long has the AC voltage been inconsistant?

flyromeo3
04-29-2009, 08:08 AM
I didnt notice this until Sunday afternoon. Also, if i look down towards the crank pully I presume, it looks like its wobbling a bit. I was staring at that thing and can swear it was moving.

I'm wondering if the Idler tensioner is the problem. Even when idling at a light my rpms slight move up and down between 800- 500

never changed any pullies.I believe im due for timing belt job anyway but i dont have 1000+ right now to get this done. Plus, im highly leaning towards selling the car once I tackle these issues.

B5A4Kevin
04-29-2009, 01:37 PM
the serp belt tensioner has a knob that accepts a 17mm open end wrench. hold it down (clockwise) to release tension while you remove the belt from one pully. then release the tensioner and work the belt off the rest of the pulleys, and finally around the mechanical fan blade (please dont try to do this with the engine running :P ).

i also vote that your alternator sounds like it is crapping out. once the battery light comes on and stays on, or you are steady 10-12v on the meter, its time to replace. make sure to get the manufacturer from the housing as stated above, flashlight and mirror are excellent for this. good luck. hope this helps.

@udikid
04-29-2009, 02:47 PM
(please dont try to do this with the engine running :P ).


^^^ haha funny

flyromeo3
04-29-2009, 04:59 PM
I got a good laugh out of that one. However, im sure theres someone out there that would try something like that.

I did some further tests:

with engine idling and everything on, a/c,fog lights,city lights,rear defroster,headlights the voltage would drop and hover a bit past 12. Upon turning off the a/c it shoots back up to near 14.

While driving and having all these things on it doesnt drop voltage.

maybe ive been driving like this for a while. I only noticed it recently since i needed to put the a/c on. NEver seen the battery light illuminate either.

audi til I die
04-29-2009, 05:38 PM
Well dude, that's a heavy load on the alternator. Especially if you have a low voltage one from factory. I think your alternator is still good and all that is just that you haven't noticed it. I know mine goes low when I have the fogs on (55w HID) but every car is different. So don't freak out yet[drive]



EDIT: I dropped voltage with my stock fogs also, so it's just the circuit that it runs off of

flyromeo3
05-01-2009, 01:28 PM
the serp belt tensioner has a knob that accepts a 17mm open end wrench. hold it down (clockwise) to release tension while you remove the belt from one pully. then release the tensioner and work the belt off the rest of the pulleys, and finally around the mechanical fan blade (please dont try to do this with the engine running :P ).

i also vote that your alternator sounds like it is crapping out. once the battery light comes on and stays on, or you are steady 10-12v on the meter, its time to replace. make sure to get the manufacturer from the housing as stated above, flashlight and mirror are excellent for this. good luck. hope this helps.


would there be enough clearance to also remove serp belt tensioner?
I ordered the belt along with a tensioner. Figured I'd replace it if its a simple bolt to remove.

B5A4Kevin
05-01-2009, 02:31 PM
yup. 3x13mm bolts iirc.

nyca4tq
05-01-2009, 06:21 PM
One way to find out if it is your alternator is while the car is running disconnect the battery. If it dies, alternator is bad. I'm not sure if these cars have voltage regulators..If they do then your needs to be checked. Sometimes they are built into the alternator so both have to be changed......Good luck.

SilverS418
10-15-2009, 08:53 AM
Did you ever solve the problem because I have the same issue in my car. The voltage drops at stops then goes up to 13.5 on acceleration . I also have a new alternator.