StratfordShark

Iceman I replaced my working hot water valve and short hose as preventive maintenance while I was doing intake refresh.

I also found it was more awkward than anticipated in terms of getting good angles on the clamps, despite having lots of room with intake off. Also found I had to get hands in awkward positions!

Afterwards I realised it would have been easier following the procedure suggested by posters here i.e. attach the short hose to valve first.

I find with lots of 928 jobs that there is often some knack/trick which once you know it means that you can repeat a job much, much faster than it took first time. Working on brakes/rotors is nice from this point of view as you can just carry over learning to the other side!

nhporsche87

Hijack!

I have heat from all my vents at all times, its a real PITA. Is this my problem? I thought I already swapped this out when the little hose between this and the block blew antifreeze all over my engine 2 years ago, but still have heat all the time in the car.

Also almost over heated 2 weeks ago when i had it out.....?

Hilton

There's several likely sources of heat in the cabin that appear to come from the HVAC system:

1. The heater valve hose with the white vacuum line
2. The comb-flap in the centre console (orange vacuum line) that mixes hot/cold air fails so that you always get too much hot
3. Collapsed engine mounts leaves a gap for hot air to enter the cabin
4. Failed temp sensor in the front wing that means the A/C only blows cold when on full-cold

The vacuum ones can either be actuators, or possibly the solenoid controller in the center console.

ckabee1

^^^ don't forget #5

5) recirc flap (in footwell) - When that fails, you will have air coming through vents even though A/C is off.

the flyin' scotsman

Wait a mo folks..............heat from the engine only comes from 1 source into the cabin.............the hot water valve; if you have issues then insure the valve is operative and vacuum is good.

If the valve is not closing to block of the hot coolant replace the valve.
If the valve is not getting the correct vacuum then theres many well documented procedures to fix.

If the recirc falp is inop...............see above.

nhporsche87

Thanks guys I'll check these out. Also, failed to mention that the neither fan was running when the motor was hot, or at all that day I should say.....

Don't know if they have ever run, that day was the first day i had driven it in temps over 50 degrees, and it was almost 80 that day.

IcemanG17

Guys I didn't replace the short little hose that is well known to fail since Devek replaced it only 14k miles ago.... Actually I was impressed at how supple it was and the return line to the top of the water pump...

backnblack

Is this valve the main reason that the heat gets stuck on?

Regards
Matt

6mil928

Good possiblity. With it stuck open hot water is steadily being sent through the heater core.

the flyin' scotsman

...........the only reason unless its red hot outside, your a/c isn't working and the recirc flap is stuck in the fresh air position.

The auto HVAC system compares in car temp to outside and sets the recirc flap while taking into account the temp lever setting to open and close the HWV. If the interior of the car is getting warmer than your setting level start with the hot water valve and go from there.