[tup1934]

Hello,
I have a 2009 BMW 328i Convertible. I am having trouble with my heater.
When I crank up in the morning I can let the car warm up and it takes about 5-7 min to blow hot air. However, when I start driving the air goes to ice cold then takes about 15 minutes to become hot again. If I just crank up and go in the morning it takes 15 min to get hot air. Any thoughts on what the issue could be?

[StradaRedlands]

Originally Posted by tup1934

Hello,
I have a 2009 BMW 328i Convertible. I am having trouble with my heater.
When I crank up in the morning I can let the car warm up and it takes about 5-7 min to blow hot air. However, when I start driving the air goes to ice cold then takes about 15 minutes to become hot again. If I just crank up and go in the morning it takes 15 min to get hot air. Any thoughts on what the issue could be?

E9x thermostats fail open, so maybe that? Any codes?

[tup1934]

No codes. Car will run at a normal temp. Just hot air takes 15 min

[StradaRedlands]

Originally Posted by tup1934

No codes. Car will run at a normal temp. Just hot air takes 15 min

Well, that was my contribution to the conversation!

FWIW heat comes through on my 330i within 1/4 mile, but my wife's 528i takes about eight miles of driving before temps come up.

[Joe_in_WLA]

I set climate control to Auto (A/C is always on) and have cold air coming out of the dash constantly. When outside temps get cold, I close the center dash vents and get mostly warm air from the floor and windshield vents.

If I were to turn off A/C, the windows would fog up. So I stick with Auto year round and adjust accordingly.

[mainbearing]

Does sound like the thermostat. Also make sure the coolant level is full.