Okay, so I think I've been getting some telltale signs. There is a slightly sweet smell when the heat is on, but it comes and goes. I'm guessing this is the smell of coolant. The windows fog up sometimes as well.

Tonight, all my windows were fogged. The only patches that weren't fogged was the front right near the windshield defogger vents. Driving like this is becoming dangerous. I'm not sure if it was the coolant leak causing all the windows to go foggy though. My socks got wet tonight while working on some stuff so that might be it, but seriously, a pair of socks shouldn't fog up every single window. By the way, it's very cold here at the moment. About 25 degree F.

The problem is I have no idea how to go about locating this coolant leak. I don't seem to be losing it very fast. I was down to about the Min line in the reservoir yesterday and that was after having topped it up about 3 weeks ago, so it's dropping pretty slowly. The heat is warm when it's up all the way, not hot. But when I drive on the highway a bit, it seems to get hotter.

Any ideas where I should start? Tomorrow during the daytime I will check to see if any of the carpetting is wet, but that may also simply be because of some snow having been tracked into the mats and stuff and not having dried out since the weather has been below freezing lately.

Thanks!
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Kenric Tam
1990 Volvo 740 base sedan (B230F)
My Volvo 'Project'