Alternator workshop (on 15lb battery), and rough idle grinding noise

[jmikola]

Yesterday, while I was driving around Philly, "Alternator workshop" flashed twice on the cluster. The first time it happened I was highway cruising and the car pretty much reset all the electronics. At the time, I had the vents on ECON and had a 400w inverter running to charge some camera batteries. i should mention i'm running a 15lb braille

it happened about 20 minutes later in a parking lot, where i almost stalled the engine (and from a quote below, this incident makes sense).

question (1) - is this a sign from above that I shouldn't be using a lightweight battery?

second issue i've been having since i got my car back a few weeks ago (it was sitting at a bodyshop from february to june) is that at low rpm cruising or more commonly idle, i get a recurring noise of 2 stutters, and a deep vibration and grinding noise. i often can feel it through the pedals, and thought it was brakes, but just having the car sit with ECON on i noticed the noise come and go about every 7-10 seconds. my last oil change was around 10,500 and i'm at about 15,700 now (will be doing another oil change within a week or so). i don't think it's overfilled oil, but could it be the fuel filter? a non-VW friend recommended dropping in a can of fuel system cleaner, which he said is always a good idea after sitting in storage for a while. i should note my mileage, esp. at cruising speed, has been fine since i had her back.

question (2) - fuel filter, oil change, or warranty work? since this is something would require me to show the problem to a tech, the odds of it actually reappearing when i need it to are slim - so i don't think that's very viable.

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researched these questions from the following threads, among others:

http://forums.vwvortex.com/zerothread?id=2447652
http://forums.vwvortex.com/zerothread?id=2319327
http://forums.vwvortex.com/zerothread?id=1722159

Quote, originally posted by Daemon42 »

regarding alternator workshop: Did you by any chance *almost* stall the engine? I and others have seen this before, when the revs drop too far such as when you very nearly stall the engine, but not quite. Basically the voltage regulator tries to maintain a constant voltage at all times, but if the alternator spins too slowly, then the voltage drops and since the engine is still running, it'll think that perhaps the alternator is shot.. As soon as the voltage returns to normal it's happy again and the error goes away.

Quote, originally posted by Dirt32 »

regarding rough idle: try your fuel filter, I know you have relativly low miles, but I had the same problem at idle my rpms would bounce a little bit and a low rpms the car would be jerky, I replaced my fuel filter at 30000 miles and it cured the above symptoms, plus the filter is only 15$ from the stealerships and takes a whole 10 min to change

Quote, originally posted by RIPPIN32 »

regarding rough idle: Found the problem plugs were fine two much oil in engine 1/2 quart high. All must not have drained out when oil change was done. Took some out reset light.

[stripethree]

Check the connection to the battery. I experienced some of the things you are describing and it turned out the negative connection on the battery/ground cable had worn (probably from all the disconnects trying to fix the damn Celis headlights) and that it wasn't getting a good connection. I don't have a permanent fix, but since I made the connection more snug I haven't seen an AW message or had any highway blackouts (which are fooking scary).

[R-ACE]

I think the Alt Workshop is most likely due to the batt. (prolly mostly because of the draw w/ the inverter + low idle) but hey, What do I know? Could turn out to be just cause your air pressure was low in the rear pass. side tire...

NO idea on the other... Good luck.

[GomobileR32]

Answer (1) Yes, most likely.

Answer (2) ??????

[rich!]

I'm running the 11.5lb for the past 2 years... I've only seen the 'workshop' message once where I almost stalled out (starting in 2nd gear and wasn't paying attention). I run the A/C everyday in South Florida, no extra electronics.

[jmikola]

Quote, originally posted by R-ACE »

I think the Alt Workshop is most likely due to the batt. (prolly mostly because of the draw w/ the inverter + low idle) but hey, What do I know? Could turn out to be just cause your air pressure was low in the rear pass. side tire... NO idea on the other... Good luck.

air pressure was topped up to 44 psi all around? was it really low at greg's gtg? or are you just messing with me

[jmikola]

Quote, originally posted by stripethree »

Check the connection to the battery. I experienced some of the things you are describing and it turned out the negative connection on the battery/ground cable had worn (probably from all the disconnects trying to fix the damn Celis headlights) and that it wasn't getting a good connection. I don't have a permanent fix, but since I made the connection more snug I haven't seen an AW message or had any highway blackouts (which are fooking scary).

i'll look into this. i did recently have it disconnected and i think there's a piece of my grounding kit still attached that was cut off and left hanging by the old bodyshop (not the one i'm currently using, thank goodness).

funny thing is, considering rich!'s comment - i wasn't even using AC because it's not charged at the moment. even before the inverter, i have noticed that the interior lights, particularly on the cluster, have been dimming slightly every so often.

[R-ACE]

I just said that...it seemed like the most unrelated thing to contribute to a AW message. I had no idea that someone (or yourself) thought they were low. Mostly because I am by no means a mech or a tech.
weird cowinkydink at any rate...

[jmikola]

some old-post bumpage / resolution.

the light dimming and random clock resets turned out to be that my battery posts weren't secured (folly #1). this was discovered at r-ace's detailing gtg earlier this month. so that was fixed up and everything has been fine since.

i also discovered that my beep when locking the car disappeared. this was discussed at the valet gtg last week. it turns out, my hood latch wasn't secured (folly #2); but don't worry, i also had hood pins on the whole time. locked the hood and the beep is back when locking again.

the rough grinding noise showed up again this afternoon. i parked the car, ran around and opened the hood, to determine where it was coming from. i was greeted with a boatload of air being blown through the engine bay - so i guess my radiator fans are working

upon further inspection, i traced the sound down to the passenger side of the engine. it consisted of a few short clicks, followed by a deep, low frequency grinding noise (between 1 and 1.5 seconds long) that loosened up at the end. my car was, again, idling at the time. any input? my car has no lights being thrown, but i'm not sure about error codes (as i don't have a vag-com handy). perhaps i should look into procuring one

[R-ACE]

So it wasn't the air pressure in your tires???
sorry, I'm no help, I guess...

[jmikola]

Quote, originally posted by R-ACE »

So it wasn't the air pressure in your tires??? sorry, I'm no help, I guess...

reading the top post over, i think i might try swapping the fuel filter. it's definitely not the oil since we did a change at your gtg.