I have a 2011 BMW 328i with a manual transmission that has an odd sweet sort smell that occurs intermittently. I smell it when the vents are on, more so with the heat, but also sometimes when the AC is enabled. It doesn't occur until the car has been driven for a bit, say 10 minutes or more. After that, it is there most of the time in the background but it is subtle, and builds up over time. I get a stronger whiff of it when I am going in and out of 1st or 2nd gear, particularly when starting out in 1st from a stop or after shifting into second to come out of a turn. Tight turns seem worse (i.e. a U-Turn). Sometimes I think I smell it when climbing a hill, but its not as consistent as when exiting a turn.
I have had the car looked at twice and we can't seem to figure it out. Because the smell is sweet, a coolant leak was suspected. The car had a leak at one point at the thermostat that was since fixed. It passes a pressure test now (I am told). Also I'm not sure the positional nature of the occurrence near/after turns or gear changes can be explained by such a leak. I would almost say its the clutch given when it occurs, but it smells rather sweet. Most clutches I have smell are much more "bitter". I also suspected a heater core leak, but there is no wetness on the carpet and no fog on the windows. I also don't seem to be losing coolant that I can tell.
Anyone have ideas on how to narrow this down? I'd like to get it fixed as the smell kind of gives me headaches and bothers my throat. Thanks
I have had the car looked at twice and we can't seem to figure it out. Because the smell is sweet, a coolant leak was suspected. The car had a leak at one point at the thermostat that was since fixed. It passes a pressure test now (I am told). Also I'm not sure the positional nature of the occurrence near/after turns or gear changes can be explained by such a leak. I would almost say its the clutch given when it occurs, but it smells rather sweet. Most clutches I have smell are much more "bitter". I also suspected a heater core leak, but there is no wetness on the carpet and no fog on the windows. I also don't seem to be losing coolant that I can tell.
Anyone have ideas on how to narrow this down? I'd like to get it fixed as the smell kind of gives me headaches and bothers my throat. Thanks
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