Heater no work so good

Originally Posted by chris98891

so if I don't need to top off after this cycle, its probably not a bubble? also, does anybody have any ideas on testing the heater solenoid? it sounds like that could be my issue now, we feel it click but don't know if its stuck

when mine went out, i just made a piece out of pipes from home depot to replace the valve to make sure that was the problem. Also, everywhere that I've read has said to bleed the following way
1. turn key to position 2 but don't start
2. turn the temp all the way up and make sure you have three red dots too
3. open the filling cap and the bleeding cap
4. pour coolant in and allow it to come out of the bleeding cap till no bubble come out anymore.

Originally Posted by LiNk504

when mine went out, i just made a piece out of pipes from home depot to replace the valve to make sure that was the problem. Also, everywhere that I've read has said to bleed the following way
1. turn key to position 2 but don't start
2. turn the temp all the way up and make sure you have three red dots too
3. open the filling cap and the bleeding cap
4. pour coolant in and allow it to come out of the bleeding cap till no bubble come out anymore.

That's the method for filling when you've drained the system. OP has a mostly full system now, so I gave him a BMW backup method, which I've read here has been added to the TIS for our model, but don't know that for certain.

Anyway, as bleeding seems to be difficult for many, including bmw techs, I thought I'd give him an alternative.

Also, have so say that even with the method you've described, you still need to check the level for days until it's stable...and then, say, once a month or so to be safe.

Update: definitely not the heater solenoid. Pulled it out, air tight when closed, fully open when triggered to open. Triggers when it should.

There was a surprisingly small amount of coolant in the hoses coming to it though. I have done maybe 5 or 6 cycles of what you told me, but the fluid level hasn't changed over the past 2.

My remaining suspects: still a stubborn bubble, interior temp sensor, or (shudder) the heater core.

Originally Posted by chris98891

Update: definitely not the heater solenoid. Pulled it out, air tight when closed, fully open when triggered to open. Triggers when it should.

There was a surprisingly small amount of coolant in the hoses coming to it though. I have done maybe 5 or 6 cycles of what you told me, but the fluid level hasn't changed over the past 2.

My remaining suspects: still a stubborn bubble, interior temp sensor, or (shudder) the heater core.

If you put the heat to the max possible and you still do not get heat then it most likely is NOT the interior temp sensor (located in the dashboard climate control face panel).

Did the heat work before the DIY?

Being out if ideas you might want to start over with a drain, remove + inspect all hoses.

Also why do you have no bobber? Didn't you replace the expansion tank as part of the DIY? Where did the bobber go? Maybe into your heater core....

Originally Posted by wildcat293

Did the heat work before the DIY?

Being out if ideas you might want to start over with a drain, remove + inspect all hoses.

Also why do you have no bobber? Didn't you replace the expansion tank as part of the DIY? Where did the bobber go? Maybe into your heater core....

My heat definitely worked before, but with how warm its been, it had probably been a couple weeks since i'd used it. I replaced the ET a few years ago as part of the cooling system overhaul, and somehow the little bobber got very frail and broke...but I was able to pull it out. The only thing left is the float that the bobber attached to

Went to my indy shop today. He's a certified BMW tech. He put it on an incline, then did basically dmax's technique, but with the defroster on and AC off.

We let it cool and eventually had to add some coolant, but the temperature got to warm at best. He still suspects it is the heater valve that has gone bad, but after blowing on the valve when opened and closed, it seemed like it works as it should. Any other ideas?

...and AC off? You had the AC on before when you were bleeding? That didn't come from me, just for the record! LOL

So this Indy's bleeding got you a little more heat, just not all you want, is that it? One, I don't know how long it was idling for in the shop, but just the fact that he got a little heat seems to me a sign that you're going in the right direction and I don't know that I'd give up on bleeding just yet...only because so many here have so many issues with it...and lots of time it's when they replaced a single component and seemed to introduce air in the middle of the system. I don't know where all the coolant goes after it leaves what's visible, but I think there are lots of good hiding spots for air.

That said...some have had luck just banging the water valve. It may be that, but I'll just say you're focused on one thing and I think you should have all the possibilities in mind. Guys have flushed out their heater core in reverse direction...same with radiator too. There's still stuff you can futz around with. And don't mean to insult you about the bleeding at all...many have issues doing this and it seems it's 90% of the reason guys don't have heat!

hahahah never even crossed my mind to turn off the ac...i have the car sitting the incline in my driveway now cooling down. he did the heavy revving at full temp, only let it cool down once before he gave it another go. Figure I'll do a few more bleeding cycles.

While doing it, he said at this temperature it should be piping hot

Originally Posted by chris98891

hahahah never even crossed my mind to turn off the ac...i have the car sitting the incline in my driveway now cooling down. he did the heavy revving at full temp, only let it cool down once before he gave it another go. Figure I'll do a few more bleeding cycles.

While doing it, he said at this temperature it should be piping hot

Start cold.

Heater on highest temp, fan on low, 3 red dots.

ET on, bleeder screw closed.

Start car. Rev to 4000K for 20 secs.

Turn off car.

Open ET cap and add coolant.

Repeat as necessary.

At some point we'll give up on this, I know. I'll let you be from now on!

Still no luck, did it 3 more times today. In other goods news, my window regulator (replaced 2 weeks ago) broke today.... in the down position. I can put it back up, it is just bitterly ironic. (pun intended)

Even better? ECS can't get me a new one until the 4th, and I have a vendetta against my BMW dealer here.

I think I'm about to say eff it and drop it off at my indy.

BREAK THROUGGHHH!!!!

Bypassed the heater valve, and had heat (but it was very engine speed specific....above 4k rpm it hits 95+ degrees from the vents, but at idle, it drops down to 65-70 degrees)

Put in the new heater valve, and same thing. Had heat at high rpms, but below 1k, temp drops pretty significantly.

Any ideas??

update, the passenger side vents are now the only ones that get warm. Its just one thing after another.

EDIT: Dmax maybe you could chime in on this...when filling the system and waiting for coolant to pour out the bleeder screw, it doesn't matter the level in the ET right? As in, you keep pouring it above the "full" mark if there are still bubbles coming out of the bleeder screw?


Sent from my ADR6300 using Bimmer

Pulled these out of the IHKA error console....the heat exchanger temp stays low, but in high revs will climb rapidly, and then return back to cold pretty quickly....these leads me to believe there is air in the system.

1. AUC Sensor
Open Circuit, error present
2. AUC Heating
Short circuit to ground, error present



I also can't figure out the error with "Heat exchanger rated temperature"

Also, are those error codes normal?

Bump.....little update on the situation...the heat works...ish.

Usually now, EVENTUALLY the driver side vents will get pretty warm, passenger side remains pretty cool. If I'm idling (at a stop light or something) the temperature of the vents drops ~20 degrees pretty quickly. Any ideas?

You probably still have some air trapped somewhere in the system. Follow the instructions posted by dmax post # 30, it worked for me. Had similar problem no heat at idle. Having the front end
of the car at slight incline such as driving up a set of ramps might help. I had to this procedure 4 to 5 times before I had heat at idle engine speeds. Good luck.

Originally Posted by alcxm5

You probably still have some air trapped somewhere in the system. Follow the instructions posted by dmax post # 30, it worked for me. Had similar problem no heat at idle. Having the front end
of the car at slight incline such as driving up a set of ramps might help. I had to this procedure 4 to 5 times before I had heat at idle engine speeds. Good luck.

It's been awhile since I've tried bleeding the system...I'll give it another try. I still fear that there are some remnants of the expansion tank bobber in my heater core, but fingers crossed that I'll never have to take it out.

Ok, this is getting iiinnntterrdasssttinnggg.

Started to warm up lately, and I've been running the AC...the driver side vents (the ones that get hot) will remain significantly warmer than the passenger side (the ones that won't warm up) when the AC is on and the car should be cooling.

So, any new ideas??

Oh, man...some issues you're having.

My only thought, based on what you've written, is that maybe you've got an issue with one of the vent doors...it happens. If I'm right, there will be a code for one...I know others have gotten them.

Just pulled all the codes...aside from the basic lambda control issues, i got:
28 AUC Sensor; Open Circuit
30 AUC Heating; Short circuit to ground

I also screenshot all of the values i pulled. All of these except the first one were at engine temperature, AC off, temp 91 degrees, middle vents.