I rarely use the heat, seat warmer are usually enough. But it's been cold lately. Whenever I turn it on I get for a few seconds what looks like smoke coming out of the vents. It gets the windows all fogged up. It does smell like coolant, but I do not see any coolant leak in the cabin. I open the windows a crack.

What is that smoke/ cloud like stuff coming out of the vents?

Anything I can do to fix that?

Thanks.
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'89 244DL M47 171K miles

Here is some info that may be useful:

http://www.sonic.net/~zipzippy/volvo/volvo%20240%20faq.html

Doesn't matter that you don't see a pool of leaking fluid -- it could be small pinhole leak that's only apparent when your engine is running and the cooling system is under pressure. There's no doubt that it's hot coolant vapors (water and antifreeze, hot) coming out and cooling and condensing into visible steam and fogging your windows. I'll bet, when you go to wipe the windows, they seem "greasy" and smear -- that's from the antifreeze component.

It's NOT a matter of WHAT it is ... undoubtedly a leak in your coolant pathway through the heating system.

The big question is WHERE! The coolant passes through the firewall, through some hoses (hose or clamp could be the culprit), through a control valve (could be the culprit), and through the heat exchanger or heater core (could be the culprit). Each of these things brings a different level of difficulty (and expense) in repairing or replacing -- the worst, of course, is the heater core.

The one thing going for you is that your car is an '89. Unless your car has been miserably maintained (by the previous owner) -- e.g., never changed the coolant -- it's unusual for the heater core (worse case scenario) to go bad this soon. Besides my '93 240s, I've still got an '84 240, and until only a couple of years ago also had an '80 240, all with the original heater core and all the hoses and clamps -- not a hint of any leak! I'm sure there are even older 240's out there with original equipment -- so if your heater core or hoses have failed, blame the previous owner!
But on the bright side, based on the above, odds are that it isn't the heater core, and you'll be facing something less difficult to fix. Here's hoping...

You'll have to pull off the panels (on each side of the center console by your legs), and poke around and watch -- and if you're lucky, you'll see the leak. If not, it's deeper inside, and harder to reach.

Good luck. May the g-ds be with you.

Thanks.
One quick question :

It produces quite a lot of heat, does that mean that the heater core is in working condition and not at fault and the coolant vapor are coming from some other leaking component (hoses, clamps, etc)?

I am not loosing any coolant as far as I can tell from the coolant reservoir... but I rarely use the heater.

Also the coolant vapors are only visible when I first turn on the heat, i.e. it seems to be happening only during the first minute or so, ten everything seems to be fine.

Thank you all.
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'89 244DL M47 171K miles

re: "...It produces quite a lot of heat, does that mean that the heater core is in working condition and not at fault...?"

Not at all -- the heater can continue to work (deliver heat to the air blown through it) while it leaks.

And it only takes a few drops of water turned to steam to occupy a lot of volume -- you probably have a miniscule leak (viz., "...I am not loosing any coolant as far as I can tell from the coolant reservoir..."), but it can grow.

My suggestion is to get it fixed, or at least confirm that it's not the heater core. Back in the mid-'60s, in college, I had a old chevy for a few months. It was a real wreck, but cheap -- then one cold night the heater core blew and in an instant, I couldn't see out any window ... steam everywhere, and every window was all coated with a greasy film on the inside that resisted wiping off ... I was lucky to pull off the road without being in a wreck!

Good luck.

Sounds like a leak in the heat exchanger, located between center console and firewall. Leaking coolant.

Check your coolant level regularly - you don't want it to run low.

I never replaced a heat exchanger. Others will post with some detail, hopefully. I think the job is pretty much a whole-day affair, or a weekend.

If you really don't need heat, you can re-route or close off hoses on the front side of the firewall. You'll see the two hoses on forward side of firewall, just inboard from brake booster, if I recall. They are not that easy to reach, but easier than the heat exchanger.
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Sven: '89 245, IPD sways, electric rad. fan conversion, 28+ mpg - auto tranny. 850 mi/week commute. '89 245 #2 (wifemobile). '90 244 (spare, runs).

Replacing the heater core is an all day if not an all weekend affair. I just recently replaced one in a heater box that I have removed and is sitting on my workbench. I removed it completely because I had to replace the cars' wiring harness from the fusebox out to the engine. Since I already had the wiring harness (and the dash of course) out of the way, I took the opportunity to go ahead and replace the core. Basically I think that Volvo took a heater core and said "Hey lets build a car around this" and that's what they did. It is sandwhiched inside of the heater box which is located directly below the center of your dash and against the firewall. I can't imagine doing this job in the car but I know that it's been done. Good Luck

re: "...Basically I think that Volvo took a heater core and said "Hey lets build a car around this" and that's what they did...."

No, you're wrong. They said, "Let's take the blower fan and build the car around it" -- and the first thing they put on it was the heater core. Ha, ha.

Regards,