Poor heat

[E30andy]

I have full on honest to god didn’t need to drive with my hat on heat!

All I did was turn the temp dial back and forth a few times while I was driving home from work today, and boom, real heat from all the vents.

So I’m assuming either the blend flap was stuck and moving the temp dial a few times freed it up, or maybe there was some corrosion on the electrical connections around the temp dial that sends the signal to the heater valve were not good and rotating it improved the signal?

Weird but there it is. Hopefully it’s fixed for good! I’m grateful to you guys for helping out!

[spdracrm3]

Yes passenger side ,there is a cable that runs from bottom of temp dial over to right side where there is a linkage for the temp blend flap it is behind and just below the floor outlet on that side of the box appears to have an adjustment too. You might be able to pull a cover off left side of glovebox opening and be able to see, it if not might have to remove the floor outlet to see.
If core is that hot its got to be an airflow issue

Sent from my SM-G360V using Tapatalk

[E30andy]

In central Finland where I live, normal winter temp is +15..-22°F. E30 heater is adequate, if everything is ok.




Did you check the hoses?

Yes, hoses are correct.
Cold ride to work this morning with temp at -12 here in VT!

[E30andy]

Well I guess there could still be an issue with the shutoff valve being powered when it shouldn't be so worth disconnecting electrical connector as an easy diagnosis.
Actually getting to the blend door requires box removal and disassembly ,but the control cable attaches to a lever on the right sideof the box right behind the floor vent so you could remove that piece and make sure lever moves thru full motion ,but you cant see the door is actually moving inside unless the core is out and then you can see it's movement thru the slot on left side where core was as you move the temp control dial. With it out you could also check airflow thru AC evaporator to make sure it's not plugged with debris or something fallen in front of it.

I have a complete hvac box out and could try to take pics ,that diagram you posted gives and good idea how things should be just not what things are on an actual case

Sent from my SM-G360V using Tapatalk

Just to clarify, by right side do you mean passenger side?

Pics would be great! Searching the web does not give me much on the blend door.

More info here....when I had the center console out and was able to feel the heater box and heater valve, they were hot. I recall the heater valve was so hot I had to pull my hand away. So it seems as if warm coolant is making its way into the cabin, but is not translating to warm air at the vents.

[muuris]

Am I just expecting too much from a car designed in the 80’s? Anybody from the arctic north car to weigh in with how their heater responds in this type of cold?

In central Finland where I live, normal winter temp is +15..-22°F. E30 heater is adequate, if everything is ok.

Previous owner put in new heater core and valve just a few hundred miles ago for what it’s worth.

First check that the heater core hoses are not reversed. The hose from cylinder head should go to the bottom connector of heater core (near firewall).

Did you check the hoses?

[spdracrm3]

Well I guess there could still be an issue with the shutoff valve being powered when it shouldn't be so worth disconnecting electrical connector as an easy diagnosis.
Actually getting to the blend door requires box removal and disassembly ,but the control cable attaches to a lever on the right side of the box right behind the floor vent so you could remove that piece and make sure lever moves thru full motion ,but you cant see the door is actually moving inside unless the core is out and then you can see it's movement thru the slot on left side where core was as you move the temp control dial. With it out you could also check airflow thru AC evaporator to make sure it's not plugged with debris or something fallen in front of it.

I have a complete hvac box out and could try to take pics ,that diagram you posted gives and good idea how things should be just not what things are on an actual case

Sent from my SM-G360V using Tapatalk

[E30andy]

Thanks again for the response Angus!
Previous owner put in new heater core and valve just a few hundred miles ago for what it’s worth.
I don’t have an infrared tool but may get one for further diagnostics.
How hard is it to get to the blend door? I would probably check that next.

[spdracrm3]

Might be time to pull the heater core and check flow thru it and also make sure temp blend door which sits right above the core is working properly

Sent from my SM-G360V using Tapatalk

[spdracrm3]

They ran the IX's on the Alcan 5000 rally up above the artic circle and in temps of -30F with no heat issues I'm thinking it has to be something in the heater box causing air to bypass the heater core or possibly a plugged core, bad valve now. Have you tried measuring temp at the core with an infrared tool?

Sent from my SM-G360V using Tapatalk

[E30andy]

So I removed the recall valve using the Prestone flush kit. Boy, that was fun....

Refilled and bled the system and after an extended drive in 2 degree weather, I hate to say, not much difference.

I get some heat with the recirc button pressed, less with it released. With the temp dialed maxed, and fan on 4, it’s acceptable but not hot by any means.

Am I just expecting too much from a car designed in the 80’s? Anybody from the arctic north car to weigh in with how their heater responds in this type of cold?

[E30andy]

I would go to parts store a get a flushing kit I think 5/8 hose size and replace the valve first with the "T" to see if it solves the issue(plug the small hose with a bolt temporarily). Then look for the replacment hose

Sent from my SM-G360V using Tapatalk

That’s a great suggestion, thanks spdracrm3!

[spdracrm3]

Sorry to keep revisiting this thread but I am really struggling with lack of heat. Now that we are having this wicked cold snap with temps below zero, the ix is basically undriveable due to the poor heat.

I’m wondering if the culprit is this “recall valve” as noted by Das Delfin. I would like to eliminate the valve to see if that restores my heat.

I’m struggling with what hose I need to use to replace the hoses used to add in the heater valve. Any help with that would really make my day!

Thanks guys!!

I would go to parts store a get a flushing kit I think 5/8 hose size and replace the valve first with the "T" to see if it solves the issue(plug the small hose with a bolt temporarily). Then look for the replacment hose

Sent from my SM-G360V using Tapatalk

[E30andy]

muuris, the temp dial is the temperature control knob to the left of the sliders in the hvac control region of the dashboard. A dial is another word for knob. Not a gauge or sensor or whatever

The temp dial (in the picture you quoted from me btw) is what governs the heater control valve. The same valve you've deleted.

If you didn't know, there was a recall for bmw in america which added another temp cutoff in place of the heater hose that flows from the t stat housing to the heater core inlet. It's a temp sensitive valve designed to cut off heat to the heater core in the event the engine overheats. This can fail and could cause problems similar to what the OP is having I thought you knew about it but apparently you didn't...

Sorry to keep revisiting this thread but I am really struggling with lack of heat. Now that we are having this wicked cold snap with temps below zero, the ix is basically undriveable due to the poor heat.

I’m wondering if the culprit is this “recall valve” as noted by Das Delfin. I would like to eliminate the valve to see if that restores my heat.

I’m struggling with what hose I need to use to replace the hoses used to add in the heater valve. Any help with that would really make my day!

Thanks guys!!

[The Dark Side of Will]

Here's the problem I found with my recirc doors:

http://phpbb.realfierotech.com/viewtopic.php?p=151910#p151910

I *may* have posted somewhere here on R3V, but couldn't find it in a five minute search.

You can pull the blower motor out and access the recirc doors directly.

[E30andy]

Dont think its the thermostat, temp gauge gets just about to 12 o'clock position and hoses feel hot to touch.