Subject: Hmmmm... Author: kharon8 : member since March, 2007 : 231 posts Posted on: 2008-01-22 04:25:04

There are two different heater valves, one to cars without auxiliary heater and one to cars with that (different part numbers). Unfortunately I've no idea what is the actual difference between there two.

You could test the valves by taking +12V to the middle prong and ground to eiher other prong (just a coil in there). If it _opens_ the valves (instead of closing), you know you have valve/control box disparity. I've no idea how you see which happens, solid *klunk* doesn't tell much. (Unless you open the valves, of course.)

If it (the voltage) does nothing, you have a/two stuck valve(s), like mine has. If I had to, I'd vote for this, a common problem.

Solenoid shaft rusts and then it starts to stick, especially at temperatures below freezing. After a while (5 to 20 minutes), warm water heats the valves and they work normally again (in mine). Until then, no or very little heat, which would fit to the symptoms you have.

I suspect the salvaged unit has been outside, standing still, a long time and thus easy to stick or even permanently stuck.

Tuomas
'89 750il
230k miles

• More IHKA problems...Help, I'm FFFFreezing (long-ish) - bimmermeister 2008-01-21 21:47:55 (176 views)
  • Re: More IHKA problems...Help, I'm FFFFreezing (long-ish) - akneppers 2008-01-22 18:15:14 (117 views)
  • Hmmmm... - kharon8 2008-01-22 04:25:04 (131 views)
    • I'll go and see mine, pictures later.... (nt) - kharon8 2008-01-22 04:26:23 (84 views)
      • ... and here they are. (pic) - kharon8 2008-01-22 09:24:05 (686 views)
        • Tuomas, yours are the version for parked heating system? - shogun 2008-01-22 10:19:03 (110 views)
          • How exactly are they different, Shogun? - steinway 2008-01-22 16:50:41 (91 views)
            • I am not sure, never have seen older one - shogun 2008-01-22 17:39:13 (88 views)
          • Yes, it is. (nt) - kharon8 2008-01-22 10:27:48 (69 views)
            • pics of repair and cleaning of aux water pump (url) - shogun 2008-01-23 04:42:45 (154 views)
              • Am I? Ouch. - kharon8 2008-01-23 04:57:28 (77 views)
                • Registered now, good pictures. Thanks. (nt) - kharon8 2008-01-23 05:10:10 (66 views)
        • Pre- pressure hole it is. - kharon8 2008-01-22 10:01:40 (97 views)
  • just had a similar problem on my E31 - Rich 1990 750iL 2008-01-21 21:58:10 (114 views)
    • Re: just had a similar problem on my E31 - bimmermeister 2008-01-24 23:43:10 (102 views)
    • 2 wire plug is for the aux water pump (url) - shogun 2008-01-22 00:34:26 (145 views)