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Litany of problems with 2002 V6 wagon; ideas?

1K views 6 replies 5 participants last post by  hu vw 
#1 ·
Hey everybody!
So, I've spent my evening so far googling/forum searching the various problems my beloved wagon is having these days. I think there may be a correlation between some of them, but I don't have enough car sense to know where to start picking these things apart. Any suggestions or ideas are appreciated.
I'll summarize past issues just for background.

Purchased 12/2013 with ~124,000 miles. All original parts save for the typically maintained, no transmission or engine work ever done (to the dealer's knowledge). No check engine or warning lights, no codes on computer. Ran quietly, perfectly.

5/2014: valve spring broke in 5th cylinder. Came back from German-specific shop with the check engine light still on. Mechanic took another look at codes but wouldn't work on it again without me shelling out more cash. Check engine light intermittently turned off and on afterward. Codes read running lean. As a precaution, changed spark plugs, wires, and ignition coil pack. No change even after a second new coil pack. Cleaned MAF sensor, no change. Couldn't afford new oxygen sensors.
12/2014: new battery.
7/2015: heard thud while accelerating quickly to avoid accident in traffic. Check engine light started flashing. Pulled over, checked oil dipstick first, and saw that oil level was very low. Bought oil and managed the 2.5 hour trip home. Check engine light still intermittent thereafter, though would often flash when coming back on. Still read lean on both banks.
11/2015: replaced burnt out headlights.
1/2016: finally could *maybe* afford a mechanic's intervention again. Took to a different import repair shop, was told it had an exhaust leak; the head tube had already been welded once, couldn't be done again, so the entire exhaust needed replacement. Quoted $2100 for repair. Couldn't afford it after all. Check engine light on much more often than off, but would stay off for some time if the battery had been disconnected.

There are other sundry things I'd done or had someone else do in between, but I don't think they're important to what's happening, except for the headlights burning out at the beginning of every winter. Pretty sure the failed cooling pump in 2017 was just because it was old.
At times, the car has been known to clunk out while trying to turn over, prompting the demobilizer to kick in and prevent ignition on the second try. These episodes have happened maybe once or twice every year since the beginning of 2016. Could sometimes avoid the demobilizer it if I lightly hit the gas on the second try.

More recently--August 2018--my fiancé decided it was time to figure out why there was a fluid leak that coated much of the underside of the car. Replaced both oil pan and transmission pan gaskets and filters at 199900-ish miles; did not replace transmission fluid with OEM or Pentosin thinking the expense wouldn't be worth it if the car was being replaced within the next several months anyway. Chose Valvoline MaxLife instead after scouring forums. Smelled transmission fluid burning for a week afterward. Shifting was more or less normal, though I noticed that it shifted from of 3rd gear to 4th at lower RPM than other gear shifts. Not sure if that existed before the transmission work.

Middle November 2018: one headlight and passenger side brake and tail lights were out. Replaced all with brand new lights, no contact with my skin. The entire passenger side tail light assembly was dark afterward, but after a jiggle on the connecting wires came back on for a day before completely going out. Took the side running light with it. Driver side lights are all on. Checked fuses, all were fine.

The day before yesterday: car clunked out while turning over. Waited 10 seconds, car turned over fine on second try.
Yesterday: battery light came on for the first time in 4 years. Figured it was just the cold weather (10ºF temperature drop overnight to mid-20s) preventing a complete charge during my 20-minute commutes to and from work. Turned off after driving a few miles.
Today: battery light came on and stayed on after the car had been idling for five minutes. Idled for another five, then started driving. Stopped for gas after it ran for 30 minutes. Started back up without issue. Shortly after starting back up I saw "ALTERNATOR WORKSHOP" on the MFD without any beeping or alert sounds. Car seemed more sluggish than usual since I started driving tonight.

The pattern of headlights burning out makes me think there has always been an underlying electrical issue, and the death of the one tail light assembly feels more convincing. Some of these other things seem like they could be associated with an electrical problem, but could be caused by other things, too. Before my dude left for the evening, he suggested that there might be a short in the wiring to the tail light, which may be draining battery voltage. Hopefully he'll have time to look at it tonight.

Thoughts?

Thanks in advance--hope this post isn't a TL;DR.
 
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#2 · (Edited)
Well for starters welcome to the forum. You're definitely in the right place to find answers.
To bad this didn't happen a year ago. I just moved from Waukesha out here to Phoenix last December. Could've had you swing by my garage.


First things first, even though it seems you have an obvious electrical issue, the fact you stated no engine service has me concerned for the timing belt and all of it's related components.
If that indeed is the case, the timing belt never being serviced, I would not start the car anymore. You are running on borrowed time with that timing belt.

Again, if this is really the case, first thing you'll need to do is get the car into service position and replace the timing belt, belt tensioner, all related pulleys / rollers (except the large camshaft pulleys) and the water pump.
During this time would be a good time to investigate the electrical connections that deal with the headlights and running lights. Those connections get taken apart when removing the front of the car (service Position).
Also a good time to check the (2) major electrical grounding points under the hood. First one being on the passengers side of the vehicle, right by the motor mount, there is a #4 gauge grounding wire that goes to the body of the car and the motor mount bracket.
Make sure those contact are clean. The second place to look is right by the coolant reservoir on the drivers side fire wall.

See arrows on picture.




To start chasing your electrical problem, first test the battery for voltage you MUST HAVE 11.4 volts minimum otherwise you will more than likely encounter problems. Diagnosing with less than 11.4 volts will give you false readings elsewhere compounding your troubleshooting efforts.


I would like to ask you before I write down a lengthy essay, How capable are you? is this something you want to tackle yourself, or is all of this stuff dependent on a mechanic at some garage?

Your answer(s) won't change if I want to help you or not, but it will change the way I write down on how to attack this animal.
The other members that chime in here will probably want to know the same thing. It just helps us give you a better direction.
 
#4 ·
The multiple burned out bulbs suggest the Voltage is too high. I would get a Voltmeter if you don't have one, they are available at low-cost (Harbor Freight, etc.). You then measure the battery Voltage as AndreasPassat said, with the engine Off. This will give a rough idea of the battery's charge, however if it starts the car, it must be working well enough. Next, and more importantly, run the engine and check the Voltage again, measuring at the battery posts, then at the battery clamps, and finally between the + post and a metal bolt or engine part. While running, the Voltage should be in the range of 14V +/- 0.5V. A little more or less is OK, but if you see serious differences between the measurements, that means a bad connection at the battery clamps, or a ground point.
 
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