I own a 2001 Passat GLS V6 (45k miles), and have recently encountered a recurring problem in my car. Particularly noticeable in cold weather, the problem seems to happen when using the heater.

Symptoms:
1. On cold days, when car is warm--->visible mist blowing into the cabin through the vents (causes windows to fog)
2. In any temp. ---> smell in the cabin (semi-sweet)

Thoughts:
1. Heater Core: The heater core might have gone bad, but it seems a little strange for a car this new. Probably looking at a ~$1000 repair (not real happy about this).
2. Other: A/C Component failure: my hunch is that this is not the case, as the problem happens most frequently when using the heat.

Anybody have any thoughts/tips on how I should proceed?

Sounds like a heater core. Other possibility - the evaporator drain may be partially clogged. With the a/c on, do you see water dripping under the car ??

I initially suspected a heater core problem. However, I haven't noticed any decline in the coolant level, which leads me to believe something else is causing the problem.

After speaking (on the phone) with the dealer service department, they thought that the Dust/Pollen filter could be culprit. Does anyone have any experience where the filter was causing the strange behavior from the climate control system?

Thanks again for all of the help.

Call VW customer service about this. I had a bad heater core in my 2000 passat. They paid for almost all the repair, even though it was completely out of warranty. I think it may have helped that I bought the car (used) from a vw dealer.

I replaced the dust/pollen filter to no avail. The vapor is still coming out of the vents when using climate control system (much more pronounced when using heat vs. A/C)

The problem is much more noticeable when the air is cold and the vapor coming out of the vents condenses to some degree. It was very visible on my drive this morning (~45 degrees F).

I need to get this fixed so I don't freeze on my way to work! Can't say that I'm extremely pleased with the possibility of a heater core failure on a 3-year-old car.

Allow me to be blunt about this. This is as cut and dry as most car problems ever get. It HAS to be the heater core. The reason you are not loosing much coolant is that it's a pin-hole leak. Also, you have not been running the HEATER, so it NOT going to leak if you never run the HEATER.

I had the EXACT SAME PROBLEM. Since I was the second owner, it was out of warranty, but VW was GREAT about it. Call VW USA 1-800 customer service line. The number is in your owners manual and a free lookup by dialing 1-800-555-1212. Nicely ask them if this should be happening in their 3 year old (or less!) cars. The ones that sell for 1000's more than honda's or Toyota's. They will most likely pay for some of the repair. But, you might even be under warranty...

There is no mystery to this (IMHO). I would call VW 1-800 customer service number before taking it to the dealer however as it is an $800-$900 repair. It may take them a day or two to review your case. You will need your VIN number (lower right under the windsheild).

In my case, the dealer fixed it for very little money, in one day, and the job was done very well. I have no squeaks or rattles, etc... Heater is perfect now. They even put in a headlight bulb for me that had gone out the day before. I had just left the bulb in it's package it in the dash. :-)

If you ask me, VW has it all over those Japanese cars (how boring they are!). But, the VW is going to cost you a bit more. Take advantage of the fact that you already spend a large sum on this car, and call VW to action about it. They should do the right thing.

Good luck,

The SMELL is the other clue here. It's not a pleasant smell, though some do refer to it as 'sweet'. It's also not the best thing to be breathing. The reason you still get some effect even with AC is that the inside of the heater box is wet. At least on newer cars, they are drained well enough (with AC system in particular, they have to be) such that this doesn't get on your carpet.) I once had an old car where the carpet was ruined by a heater core leak.

bpick - thanks for the insights. I was a little skeptical (and perhaps hopeful) that it was not the heater core, as the car was <3 years old and the repair is fairly expensive.

Had an interesting epidsode with the car on the drive home from work on Friday....it now is sitting on the dealer's lot awaiting diagnostics. The coolant resevoir completely emptied, nealy causing an overheat. I'm guessing that the earlier problem was related to the incident. We'll see what the repair shop tells me this week.

Thanks again,

j12

Sorry to hear that. I hope it's not too late to ask veedub about chipping in for this. It should not have happened--sounds like VW got a few bad heater cores...

If it's any consolation, mine is in the shop today, too, getting an EMISSIONS WORKSHOP! message cleared... and maybe some break work. (I hesitate to get it done at the dealer's but OTOH, I want it done right...)

Good luck!

The bill for this one was not pretty. Picking up my car, and emptying my bank account, I was taken for $1300 for the entire show. Ironic that I bought the newer car to avoid unscheduled, costly maintainence occurences in the first place!

Approx $1000 went for the heater core, 90% for labor. VW designed the car to necessitate removing the entire dash to access the heater core.

Approx $300 went to the emissions workshop, which was the replacement of a secondary vacuum line.

Not such a big fan of VW right now!