Hi, maybe this will help to someone who have problems to get heat inside.

I have L322 4.4L gasoline (2003) with aux heating. Lost interior heating gradually during summer and now when autumn arrived, its started to be really cold to drive.

Symptoms: Engine heats normally but no heat to inside, aux heater was running for only short period.

Checked the water pipes which goes to inside heater matrix. Some of those pipes where mild warm some just cold (tad difficult to check as engine was really hot next to hand).
Water valve behind the engine (pita to change) was the issue. It controls which water goes to heater matrix (engine or aux heater). the seals inside were swallowed and blocked.
I ended up changing also dual water valve next to suspension tower (easy to change) as it's old and cheap.
Recommended to buy BMW valves as those are cheaper than RR versions.

Below some pics.

small valve behind engine



Somehow pics are not uploading??

Here are the EOM codes for the Water Heater Control Valve LR066865 / LR040731 / JEO000010 / 6421690744402

Tom1973 wrote:

Water valve behind the engine (pita to change) was the issue. It controls which water goes to heater matrix (engine or aux heater). the seals inside were swollen and blocked.

Tom1973 wrote:

I ended up changing also dual water valve next to suspension tower (easy to change) as it's old and cheap.
Recommended to buy BMW valves as those are cheaper than RR versions..

Aux heater = webasto (fuel burning heater)

BMW code for heater valve is 6421690744402

Thank you.

Was the FBH only on diesel powered vehicles? Ron B. VK2OTC
2003 L322 V8 Auto
2007 Yamaha XJR1300
Previous: 1983, 1986 RRC; 1995, 1996 P38A; 1995 Disco1; 1984 V8 County 110; Series IIA

FBH was option for gasoline version too, just more rare and maybe only for Nordic countries (mine is that).

Does it have a separate diesel fuel tank or does it burn petrol? Ron B. VK2OTC
2003 L322 V8 Auto
2007 Yamaha XJR1300
Previous: 1983, 1986 RRC; 1995, 1996 P38A; 1995 Disco1; 1984 V8 County 110; Series IIA

it burn petrol

I have one too on my UK 2004 AB. It was an option (and a bloody god one too!!)

It runs on Petrol.

Thanks gents. Ron B. VK2OTC
2003 L322 V8 Auto
2007 Yamaha XJR1300
Previous: 1983, 1986 RRC; 1995, 1996 P38A; 1995 Disco1; 1984 V8 County 110; Series IIA