[Herakles]

And its begun.. 2011, 65K miles, stock pretty babied car. Just had in the last month happen:

-Valve cover gasket leak (not repaired yet)
-Coolant leak (replaced radiator about 2 years ago not sure where leak is now)
-Heater not blowing HOT air **concerns me the most**

I thought since i have been topping off the coolant maybe it got too low and air got in the system. I bled the system using the auto bleed procedure. Upon completion, i felt some hot air coming through the vents, but lasted maybe a few seconds and stopped.

Any ideas? Water pump works, we know that so far.

[gbalthrop]

If you have owned the vehicle more than 5 years, WHEN did the lack of heat BEGIN?
When did the coolant leak (one now as opposed to 2 years ago) begin?
If you select DEFROST (button on Right of Climate Control Panel) with engine warm, does HOT air come from windscreen vents?
Is temperature of air discharge from ALL vents on Right & Left sides of car the same?
Do all the buttons for air discharge direction WORK? Footwell, Facia, Windscreen?
Does A/C or Cooling Function of Climate Control System function as it should?
What Scan Tool or Diagnostic Software do you have?
Do you have a Windows OS Laptop?

There are a number of things other than lack of coolant flow through the Heater Core that can cause lack of heat with warm engine. There are "Mixed Air Flaps" on either side of the unit that direct cool air though the Heater core, or NOT, per Thermostat Setting on EACH side. There are wiring or component faults which can occur in the control of those Flap Motors (8 of them) and cause lack of heat.

INPA (BMW Factory-Level Software) can quickly give you Live Data of Flap Positions and allow you to see if the Motors are operating to change flap position when you operate the different controls on the A/C Control Panel.

Let us know answers to questions above, as well as ~ amount of coolant lost per hour of engine operation, and we can sugget next steps.

George

[cisf0rcalvin]

I had a problem with no heat/slightly warm air and it turns out my heater core was plugged. There were no codes.

Check this PDF out from bimmerfest forum. I was able to flush the core and a lot of little bits came out of it. Heat worked great afterwards.

I did not raise the car to do this. I just took out the airbox and unhooked the two hoses from the top and let the coolant drain that way.

[Herakles]

For a second I thought i had to dilute the coolant I was getting from autozone but it's fine I add it straight this is what I been using since coolant leak

[Herakles]

Originally Posted by gbalthrop

If you have owned the vehicle more than 5 years, WHEN did the lack of heat BEGIN?
When did the coolant leak (one now as opposed to 2 years ago) begin?
If you select DEFROST (button on Right of Climate Control Panel) with engine warm, does HOT air come from windscreen vents?
Is temperature of air discharge from ALL vents on Right & Left sides of car the same?
Do all the buttons for air discharge direction WORK? Footwell, Facia, Windscreen?
Does A/C or Cooling Function of Climate Control System function as it should?
What Scan Tool or Diagnostic Software do you have?
Do you have a Windows OS Laptop?

There are a number of things other than lack of coolant flow through the Heater Core that can cause lack of heat with warm engine. There are "Mixed Air Flaps" on either side of the unit that direct cool air though the Heater core, or NOT, per Thermostat Setting on EACH side. There are wiring or component faults which can occur in the control of those Flap Motors (8 of them) and cause lack of heat.

INPA (BMW Factory-Level Software) can quickly give you Live Data of Flap Positions and allow you to see if the Motors are operating to change flap position when you operate the different controls on the A/C Control Panel.

Let us know answers to questions above, as well as ~ amount of coolant lost per hour of engine operation, and we can sugget next steps.

George

Thanks
Actually the coolant was flushed a few years ago after my first leak when I had radiator replaced

I bought the car like new with 9k miles in 2015 so don't suspect anyone added any patch crap in coolant system

The valve gasket leak has been going for a few months now

Hear doesn't come from anywhere defrost, or anywhere else.

Wonder do I take it to Indy shop or bmw ugh

[longm1985]

Thermostat stuck open (some cars this can do it, not sure about BMW though)? Does it get warm AT ALL? If you can, use a scan tool and watch your coolant temp.

[Herakles]

I dont think its thermostat- the car goes up to temp if it was stuck wouldnt the temp gauge stay pegged closed?

I checked the heater core hoses- one felt hot the other just warm which makes sense one is in and other return so good news there

There is coolant (i do have a coolant leak and I top it off)

There is no hot air anywhere, not even defrost.

[clegg]

You should be using the Blue Coolant, The violet is for VW, Audis etc. Probably not a huge difference but the blue is for BMW.

What happens if you move the knob just below the center vents to the right?

[Herakles]

Originally Posted by clegg

You should be using the Blue Coolant, The violet is for VW, Audis etc. Probably not a huge difference but the blue is for BMW.

What happens if you move the knob just below the center vents to the right?

ahh i wish was something like that, nothing really i had it far right to red and in middle no difference.

So ruled out:

-Water pump: ran bleed cycle no issues.
-Coolant: good
-Thermostat: the temp goes up to normal operating range (175ish?)
-Blend door: I check for heat on defrost, floor, and vent no heat at any setting
-Heater core: Touched both hoses to heater core, one felt warm, other felt much warmer, believe that is normal. Almost original owner of car dont think anyone put additives
-Blower motor: my fan works high low, not that.
-Valve cover gasket leak: i would think not contributing. Just smokes smells when car is parked at right slope to leak on the cat

What else have i left out?

[cisf0rcalvin]

Flush the core! If one pipe is a lot warmer than the other, I'm pretty sure its not flowing correctly. Heater core shouldn't remove that much heat from the coolant.

[Herakles]

Originally Posted by cisf0rcalvin

Flush the core! If one pipe is a lot warmer than the other, I'm pretty sure its not flowing correctly. Heater core shouldn't remove that much heat from the coolant.

Why would I never used a sealer. I think it's the heater control valve. Isn't one hose supposed to be warmer than the other one is a return that's cooler right ?

[Herakles]

Wanted to update;

The shop found the radiator had a crack , it was replaced 1.5 years ago and was covered under warranty. They flushed the coil too but said not much came out and must of been just the air from the cracked radiator