undacovalova

Hi guys as some of you have known i was having problems with heat. Good news is that i think i may have narrowed it down a lot. Today i was trying to bleed the coolant the manual way not automatic, which is open expansion tank let the car run till operating temp and when the electric fan comes on means that its finished. Anyways i waited and it finally got to operating temp and i started to feel the hoses connected to the water valve, and none were hot. Not the inlet or hoses running to the heater core. Well the ones running to the heater core made sense...no heat in the car. But the inlet one from what I've gathered should be equally as hot as the other coolant parts of the car. Well it isn't, which has lead me to believe that coolant isn't making its way to the water valve.

This is where i need you guys, i was wondering if you guys would have any idea why the coolant wasn't making it to the water valves. I think i may have traced one of the hoses back to the "supply coolant hose". Its a kind of coolant neck off the radiator that branches one small hose off which i think connects to the water valve, and the upper radiator hose. The thing is upper radiator hose is hot but the small hose is cold? maybe its a thermostat of some sort stuck :S Any info is greatly appreciated.

Thanks

Randy

AUSaxon00

From my experience, the main causes of a lack of heat in the cabin are:

1. Low coolant level
2. Malfunctioning thermostat
3. Malfunctioning coolant pump
4. Blockage within the cooling system that restricts flow

It sounds like you have remedied #1 above. You may want to see if any fault codes are stored in the DME to troubleshoot #2 and #3. Have you had any issues with the engine overheating as evidenced by warning messages from the iDrive? If so, then #3 may be the issue. The electric coolant pump in my 2006 525xi failed at 90k miles and I lost cabin heat very quickly, followed by a rapid engine overheating. If you've run with a significantly low coolant level for any period of time, you may have also damaged the coolant pump. Performing a complete coolant system flush and fill may remedy #4 if the blockage is not too severe.

undacovalova

no overheating, so not thermostat.
coolant pump whines when doing auto bleed, so no malfunctioning coolant pump.
There is a blockage in that hose cuz its not hot. Im gonna take it off and see if coolant comes out.

undacovalova

nobody knows?

guysk8r1717

ever think your thermostat could be stuck open?i have same issue,low heat,checked with heat gun on upper and lower hoses after a very long drive and 153 top hose and 130 bottom telling me thermostat is stuck open,but maybe im too used to domestic vehicles with its simpler design,i dunno just a thought

undacovalova

ye but with inpa it shows that the car is warming up right to about 101 degrees?

twh

Have you looked at the part called (4) in this diagram? This is a valve that controls water into the heater core.

http://bmwfans.info/parts/catalog/E6...ose_ihka_high/

I've had two cars in my lifetime that had problems in similar parts that caused no heat. One 80's Mercedes (electrically controlled valve) and one 70's Pontiac (vacuum controlled valve). Typically these values prevent cold water from coming into the heater core until the coolant heats up to some minimum level. In the Pontiac case, I just removed the value and put a piece of pipe to connect the two hoses. That isn't optimal, but it works. In the Mercedes case, the diaphragm inside the valve was punctured and nonfunctional, so I replaced the valve. The same Mercedes also had a flaky Automatic Heat/AC unit (the inside buttons) that I repaired. There were some internal solder joints that had cracked, so sometimes they worked and sometimes not.

You should be able to see of this valve is opening when you have the heat on max and the fan on. Alternately, you can put a piece of short pipe in place of (4) and see what happens. If heat works, you need to replace (4).

chamilun

I second the water valve. The x5s have this problem a lot. Not sure about the e60s.

by the way, the way I bleed the system is like this.

Fill to brim.

turn key to position 2 (not started), turn heat to as high as possible and turn fan to high.

More fluid will be pulled into heater core.

fill to brim again. you will see bubbles. as bubbles subside and level stabilizes,
open the bleeder screw(s) a bit and let the air out, again checking the level.

drive the car and warm it up (with cap on of course). no slowly open bleed screws. air will hiss out. Once you have only
liquid coming out the air should be gone.

ctcoin

Have you ever had heat in the car? At what temp is it outside when you notice you have no heat? I fixed the heat in my 530xi. It never had good heat especially below 20F. Some 5 series did NOT come with an auxiliary heater pump and so they do not get enough heat when it gets very cold out. It is a design deficiency in the car. Let me know...

pcy

There is no design deficiency. If the heat is not working in your car, some thing is wrong. You can have it fixed [by a qualified tech] or you can call it a design deficiency and live with it :-)