Smell from vents

[afree]

I have a 2008 (May 08) XC70. About 3 months ago I started smelling a "sweetish chemical like" smell from the vents for the first minute or so of driving. This is not a bad odor that I would associate with mould or something in the vents - I figured it had to be antifreeze and I figured I had a leak. A few days later a warning light came on that said coolant low - service immediately, or something like that. I took it to the dealer and they said it needed a 1/2 cup of antifreeze (which I guess is not that much for a year old car?) - it was just hitting the low mark on the fill tank. I also asked them to do a pressure test of the system - which they did. They said the system held pressure for the half-hour or so under pressure. However, the smell persists - any ideas on what this could be - it is minor, but annoying. The smell goes away after a while, but if the car sits for a few hours it is noticable when you start. If anyone has advice on this it would be appreciated.

AF.

[Lotus99]

This is the strangest thing! Just today when I started the car, I smelled that too, and thought nothing of it since it wasn't that bad (I'm used to occasionally in cars smelling a bit of mouldy smell initially given the condensation that's left over from the A/C working). Now I know at least I wasn't dreaming of that smell!

[afree]

Definitely not dreaming, I took it into Volvo a month ago, even had the service "greeter" (don't what else to call those semi-clueless people at my local Volvo dealer that try and convince you it is all your imagination and that it is perfectly normal) tell me the smell was "not that bad" - I mean, why should I smell ANYTHING other than fresh (ok, not that fresh in the city) air. Anyhow, if anyone can shed light on this one - I'm pretty sure what I am smelling is antifreeze, but a pressure test of the system *should* detect a leak, even a small one, I would think.

[mbsl98]

I have a 2008 (May 08) XC70. About 3 months ago I started smelling a "sweetish chemical like" smell from the vents for the first minute or so of driving. This is not a bad odor that I would associate with mould or something in the vents - I figured it had to be antifreeze and I figured I had a leak. A few days later a warning light came on that said coolant low - service immediately, or something like that. I took it to the dealer and they said it needed a 1/2 cup of antifreeze (which I guess is not that much for a year old car?) - it was just hitting the low mark on the fill tank. I also asked them to do a pressure test of the system - which they did. They said the system held pressure for the half-hour or so under pressure. However, the smell persists - any ideas on what this could be - it is minor, but annoying. The smell goes away after a while, but if the car sits for a few hours it is noticable when you start. If anyone has advice on this it would be appreciated.

AF.

If your warning light was on, it took a good bit more than 4 ounces to top it off, more like a quart/liter. And no, I would not expect a one year old car to need antifreze added. I generally don't add antifreeze to any of our cars between 2-year changes, and mostly they are quite a bit older than that.

The only place that antifreeze can enter the cabin air stream is through the heater core and its related water hoses/o-rings. Even then, hose and o-ring leaks are usually external and not in the air flow, so most likely it has to be something to do with the heater core itself. I would expect a pressure test to show something if you can smell it, but perhaps it has to do with the test being done on a cold system, while actual use includes getting it all quite hot and repeated heat and cooling cycles that may open tiny leaks.

Nest step I would do is put a mark on the side of teh coolant tank, and record the date and miles. Then pay careful attention to when the level drops. I would guess that your level was pretty constant for much of the first year, and that it started to drop around the time you began noticing the smell. If so, you may find that it is dropping faster than "1/2 cup over a year" would suggest, and that knowledge would be good fodder to go back to the dealer with.

[afree]

Mike, this is extremely helpful, thanks.

AF.

[mgbannister]

Did you ever figure this out? I have the same thing but only when I turn the a/c off. It only lasts for a few minutes - usually I just turn the a/c back on and it goes away almost immediately.

Any other ideas?

[afree]

Not yet, I'm going to monitor my coolant level closely - it does have something to do with using the AC then, letting the car sit, then after several hours restarting - doesn't matter if the AC is on/off when you restart. As Mike pointed out, could be a leak in the heater core, only happens when the car is hot. It will probably take few months for me to figure this out - if I do I'll post it here.

AF.

[Mighty Quinn]

I have a 2008 (May 08) XC70. About 3 months ago I started smelling a "sweetish chemical like" smell from the vents for the first minute or so of driving. AF.
Are you sure that it wasn't a "Swedish chemical like" smell? [cool2]