[echo1912]

Got a 2011 328xi with no heat. It’s a little uncomfortable here in IL when the temp is below freezing. Had my radiator replaced about a year ago when I bought the car. Ever since I got it back from that ive had no heat. It’s warm air but not hot. Was thinking it’s a the thermostat but it looks like the car does get up to temp. Any help would be appreciated. I’m trying to stay away from shops and do the work myself but also don’t want to get to deep into it as it’s my daily car.

[BashShah]

Properly diagnose your issue.
Yes it sound lke your Thermostate but it could be:
Temp knob is on COLD...
or heat/cold actuator flaps are stuck.... in the Cabin.

if you Rad Fan on at full speed at cold startup or after like 2 min from cold start?
if so, it's your Thermostat. replace both water pump and Thermostat.

[echo1912]

Originally Posted by BashShah

Properly diagnose your issue.
Yes it sound lke your Thermostate but it could be:
Temp knob is on COLD...
or heat/cold actuator flaps are stuck.... in the Cabin.

if you Rad Fan on at full speed at cold startup or after like 2 min from cold start?
if so, it's your Thermostat. replace both water pump and Thermostat.

The thermostat has been replaced about 3 times in the last year because the shops keep thinking it’s that. And also the water pump is new. All the buttons are setup in the cabin right. Itll blow hot air when I’m not moving but once I start driving it gets cold. Was thinking blend door actuator maybe.

[E93Dude]

Have you hooked your car up to your code reader? Are you reading any fault codes? That is usually the first thing to check with any problem on a car.

As a possible CHEAP fix, and absent fault codes, have you heater core FLUSHED. Don't just CHANGE the coolant - have it flushed with a specialty product. You can do this by flushing the entire cooling system from the radiator, or just hook up to the heater core inlet/outlets ports by the firewall. A 3-series like yours has nearly 14 years of corrosion and deposits built up in the heater core. A clogged heater core can reduce its ability to transfer heat into the cabin. This problem started after you had the old radiator replaced, so its possible that procedure jostled some of the crud in the heater core.

If that doesn't fix the issue, I suspect it may be the HVAC flap actuators - not sure, but I believe fault code reader might show that.

[Ariakas]

Originally Posted by echo1912

The thermostat has been replaced about 3 times in the last year because the shops keep thinking it’s that. And also the water pump is new. All the buttons are setup in the cabin right. Itll blow hot air when I’m not moving but once I start driving it gets cold. Was thinking blend door actuator maybe.

I have the same problem after upgrading to CSF radiator for my e90 335i. New water pump, new thermostat did not fix issue. Based on my research and BMW tech input, the radiator is too efficient. I read in this forum to cover the grills to block the cold air to radiator, I have not tried it.

[echo1912]

Originally Posted by Ariakas

I have the same problem after upgrading to CSF radiator for my e90 335i. New water pump, new thermostat did not fix issue. Based on my research and BMW tech input, the radiator is too efficient. I read in this forum to cover the grills to block the cold air to radiator, I have not tried it.

I have been recommended to block part of it also but that sounds like it could cause problems. I also a bmw tech tell me my radiator was too efficient. Guess I’ll never have to worry about it overheating lol.

[echo1912]

Originally Posted by E93Dude

Have you hooked your car up to your code reader? Are you reading any fault codes? That is usually the first thing to check with any problem on a car.

As a possible CHEAP fix, and absent fault codes, have you heater core FLUSHED. Don't just CHANGE the coolant - have it flushed with a specialty product. You can do this by flushing the entire cooling system from the radiator, or just hook up to the heater core inlet/outlets ports by the firewall. A 3-series like yours has nearly 14 years of corrosion and deposits built up in the heater core. A clogged heater core can reduce its ability to transfer heat into the cabin. This problem started after you had the old radiator replaced, so its possible that procedure jostled some of the crud in the heater core.

If that doesn't fix the issue, I suspect it may be the HVAC flap actuators - not sure, but I believe fault code reader might show that.

Yeah I hooked up a reader and no fault codes popped up. I’m going to try the core flush next. Hopping that will fix the problem.

[ptpending]

you need not only do good core flush, but also correct fill after that, without air bubbles