[mdf]

2018 230i coupe. 30K miles. I am occasionally smelling coolant in the cabin. Car is new to me ~6 mo ago. I can't reliably reproduce it, like if I run the heater or defroster, but I notice the coolant smell most often if the car is idling on a downhill or driving a slow downhill. Then I smell coolant. Checked the fluid level manually (on a flat) and level looked low but ran the iDrive routine and it said coolant level was okay. Don't see any drips on the garage floor.

Any similar experiences, advice? Thanks.

[cooolone2]

When you smell it have you checked to see if the carpet is wet on either side? Typical (other cars) is when you can smell coolant in cabin it's a heater core leak! Might be very small... But if you're not losing coolant than who knows, that would be weird!

[mdf]

Thanks. I haven't checked the carpet. I'll give that a try next time I smell it. I also thought about heater core, but I would expect to smell it when running heater or defroster. I also can't think of anything in/related to the car that smells like coolant, like I am smelling something else not coolant.

[cooolone2]

It could be a very small leak that's burning off when on the engine. I had one like that on my E46, was a pin hole! Amazing because otherwise no other details of a leak... Lol.

Track it down... Try jacking the rear of the car up (not in gear, lol) with engine running and try to duplicate it... Might be easier to find than while driving.

[mdf]

Originally Posted by cooolone2

It could be a very small leak that's burning off when on the engine. I had one like that on my E46, was a pin hole! Amazing because otherwise no other details of a leak... Lol.

Track it down... Try jacking the rear of the car up (not in gear, lol) with engine running and try to duplicate it... Might be easier to find than while driving.

Good tip. Thanks!

[mdf]

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