Cold A/C on passenger side and hot air on drivers side.

[geargrinder]

Hmmm.... I suspect INPA is correct...

Santa basically are you saying that the system won't act up now that you have INPA connected? Maybe indeed your low voltage incident caused some glitch. Normally a basic disconnect resolves that... but stranger things have happened...

In this situation, having the 'stratified' control set to full hot would not / should not give you actual hot air if the heater core control is working properly. AKA if the heater core is not being heated (because its hot out and the AC is solidly on) then the heater core isn't going to warm up therefore you will see roughly the same cold-air temp anyway... (because the heater core is always supplied with the cold-air source anyway). The stratefied control is more about doing the opposite... bypassing the heater core for fresh-air when the heat IS on...

Not sure if there's anything here but this is the factory E39 HVAC training doc... might be spur some ideas... The overview diagram on page 8 is pretty good to illustrate how the stratify control bypass works - it controls those middle valves to modulate between cold and hot air for the face vents only...
https://www.slideshare.net/fajarisna...irconditioning

[Santaclaus4]

Good news everyone (since I'm the one that is buying the parts), it failed again while I was driving and had INPA running. I got a hint of warm air and looked at the data screen and I could watch the drivers side heat exchanger temp rise from 41°F clear up to 204°F. The evaporator was still around 37°F and the passenger side remained at 41°F.
I changed to the digital page and could see both water valves were being driven closed. I changed the temperature on the cars HVAC digital display from 90°F down to 60°F. I could watch the passenger side water valve shuttle from closed to open but the drivers side remained closed.
I manually cycled the water valves

(using INPA)

and the drivers side began operating normally for a while before it failed again.
One thing I'm trying to figure out however. I'm thinking that the INPA digital page shows the water valves being driven open or closed, not what their actual position is. If that's true, how come the driver side water valve showed it was closed (or being driven to close). If it was stuck open, how come it cycled when I selected that in INPA. Maybe because it was a longer pulse width (50%) using the computer verses the car driving the valves for a much shorter duration?
I realize this post is kinda "wordy" and long but I'm trying to understand the data or maybe just overthinking.
It's likely that the valve is just getting stuck. I'm gonna order the whole pump and valve assembly from FCPEuro and hopefully be done with this. I wanna be able to drive my car. It's too pretty to be a hangar (well, garage) queen.

[JimLev]

There is no feedback to let you know the valve is actually closed.
When you get the new assy it would be good to see if there is junk inside the drivers side solenoid plunger.

[OrzechNJ]

You guys right. The part I bought is meant for i6s Im gonna buy a rebuild kit and hopefully this solve my problem
Thanks

[geargrinder]

Yeah... I’m generally against the parts cannon, but i might go w the whole assy, as long as it’s not too $$$. Gives you the peace of mind of all the parts of that assy being refreshed...

[Santaclaus4]

I replaced the water valve and pump assembly a few days ago. So far it's all working as it should. Barely any coolant came out when I took the valve assy off. I didn't even need to add coolant. Now when the heat is turned up (key on, engine off), the pump actually activates and circulates water. It wouldn't do that before. The new valves work and sound slightly quieter than the old valve assembly when activated by INPA.
When looking into the water fittings on the old valve body, I don't see any corrosion or damage like I've seen in other postings. I purchased the car from the original owner five years ago and they kept up on MTX so maybe there won't be any corrosion.
I haven't manipulated the valves to see if they are getting stuck. I will disassemble the old valve body and pump assembly and see what's going on inside. I'll take plenty of pictures. Hopefully the forum picture issue will be fixed by then so I can upload them.

[Santaclaus4]

I have an interesting observation. Since I replaced the watervalve/pump assembly, my A/C has been much colder. This summer I've been thinking my air conditioning needs to be recharged. It hasn't been as cold as it had been. It wasn't consistant though so I wasn't sure. I suspect the water valve had been starting to fail for a while, allowing hot water to leak into the heater even on a hot day with the A/C turned on.

[Santaclaus4]

I just notice something slightly interesting. In addition to being able to have the "heat" on with the engine off at initial shut down, I can also turn it back on while (for example) loading groceries after going shopping. Turn the key to position one (1) and hit the max button. Apparently even though the engine has cooled down a bit, you can still run the heat to warm the cabin up and clear the windows without running the engine. Trivial and not quite worth posting but since I all ready have this thread started...

[computiNATEor]

I just notice something slightly interesting. In addition to being able to have the "heat" on with the engine off at initial shut down, I can also turn it back on while (for example) loading groceries after going shopping. Turn the key to position one (1) and hit the max button. Apparently even though the engine has cooled down a bit, you can still run the heat to warm the cabin up and clear the windows without running the engine. Trivial and not quite worth posting but since I all ready have this thread started...

Yep, that’s the button that used to be labeled “REST” in pre facelift cars. It’s a neat feature:
https://www.bimmerforums.com/forum/s...7#post11185657