heater not working

[Leonardas]

Help, I can get almost no heat from the
heater on the '97 318ti. I had this fixed
once under warranty. I just had a new
thermostat installed, so that's not the
problem. I was looking at the electrical
diagram in the Bently manual and the heater
system is electrically operated. Does
anyone know if it's usually the control
model that goes bad or is it the heater
valve/solinoid?

Thanks,

[ayton]

bleed the system for air. check the bottom return hose on the left side of the radiator if its cold, you have air.

[This message has been edited by kinkajou (edited 01-15-2003).]

[Sparco]

I have the same problem and i did bleed the radiator and my heater still barely works. Any other reasons that it might not be working. I have a 95ti

[Sparco]

I have the same problem and i did bleed the radiator and my heater still barely works. Any other reasons that it might not be working. I have a 95ti

[1996 328ti]

Two problems.
One it could be a loose cable to the temp knob in the dash. You would need to remove the glove box and knee bolster. Pop the cable back on and secure it witha small screw so it doesn't happen again. There is actually a BMW bulletin on it.
Two it could be your bypass valve. It's located near the firewall. It's much easier to replace than taking apart the dash. I think you should be able to feel warm water going through one of the hoses if it's working.

When I had my car in a couple years ago, the tech took apart the dash and added the screw. The cable did not pop off though. He then replaced the bypass valve. Now I'm warm and toasty.

My money is on the bypass valve.

[Sparco]

thanks however we checked the bypass valve and the hose is hot..and could you direct me to that bulletin??..thanks alot

[ayton]

how did you bleed? when I did mine it took me the better part of 2 days and a couple of test runs in between... I finally positioned the car in the driveway and ran it with the cap off until anti freeze gurgled and spilled over the top (all the air was out) the level dropped and I topped it up.

[Sparco]

there was a screw on the top of the radiator that the handbook said to take out and fill the radiator to the top to push out all the air.

[1996 328ti]

I saw the bulletin at the dealer. I don't have a copy of it. Sorry.

[ayton]

yes that is the bleed screw...use both ways to get the air out ...I know it's a pain.

[Leonardas]

I still can't get my heater to work. I tried bleeding the system multiple
times. using the bleeder screw and pressurizing the system slightly.
I tried replacing the heater valve. I took the glove box out and can
see the linkage moves when the heater control is turned. The hose
from the heater valve going to the firewall feels hot. Any ideas?

Leonard

[caffeinekid]

Does the TI impliment a classic heater core or is that what the "valve" you are referring to is? I had a blocked heater core on a Peugeot once with the same symptoms. No leakage or anything, just cold air in the compartment. Brrr.

Is there a fuse for the control module?

[J!m]

I suppose it could be blocked, particularly if you have a '95 that never had the cooling system flushed out and/or came from a warm climate where the heater did not get much use.

Since the valve stops the water flow to the core, crap will collect there due to inactivity. in extreme cases, it will corrode the core, and cause the sweet smell of glycol in the carpets!

Just like cycling the A/C compressor every month (your defrost will work 100% better with the compressor on by the way), so should the heat be cycled every month.

It's like they say, the worst abuse for a car is not using it. I hate storing my car for the winter, but I start it every month, and do my heater and A/C cycle. I let the car run until the aux. fan turns on (I have the engine fan now with the 3.2 so it takes a good 1/2 hour-45 minutes to get hot).

If it's not too much trouble, you could pull both hoses from the firewall and feed the garden hose into one side and observe the water flow from the other. It may be all brown and nasty and if so, flush it until the flow is high and the water clear. After it's all back together and bled of air, check the 'potency' of the anti-freeze with one of those testers. It may end up a bit weak from the water in the heater core. I would also schedule (or do) a complete flush-n-fill in the spring to get that tap water out of the system. It's not much, but it can scale up and, as much as I'd like to sell you my 1.9, I doubt you want to buy it when you over-heat yours and warp the head...

[bucksworld]

Originally Posted by J!m

I suppose it could be blocked, particularly if you have a '95 that never had the cooling system flushed out and/or came from a warm climate where the heater did not get much use.

Since the valve stops the water flow to the core, crap will collect there due to inactivity. in extreme cases, it will corrode the core, and cause the sweet smell of glycol in the carpets!

Just like cycling the A/C compressor every month (your defrost will work 100% better with the compressor on by the way), so should the heat be cycled every month.

It's like they say, the worst abuse for a car is not using it. I hate storing my car for the winter, but I start it every month, and do my heater and A/C cycle. I let the car run until the aux. fan turns on (I have the engine fan now with the 3.2 so it takes a good 1/2 hour-45 minutes to get hot).

If it's not too much trouble, you could pull both hoses from the firewall and feed the garden hose into one side and observe the water flow from the other. It may be all brown and nasty and if so, flush it until the flow is high and the water clear. After it's all back together and bled of air, check the 'potency' of the anti-freeze with one of those testers. It may end up a bit weak from the water in the heater core. I would also schedule (or do) a complete flush-n-fill in the spring to get that tap water out of the system. It's not much, but it can scale up and, as much as I'd like to sell you my 1.9, I doubt you want to buy it when you over-heat yours and warp the head...

I have the same problem and I live in Florida it's just starting too get real cold. Man' I just might live without it. This seems like a lot of work and money. The heater core, that valve thing and the cable. Plus u have too bleed the hell out of it. I only got two more cold months. I will do the new hoses and thermostat and flush w/bleed. If that does not do it, I'll
give it up and pray for a mild winter.

By the way, what kind of water does one use? Distilled?

And just in case; how do u work on the heater core? Do u need to take the intake manifold off to replace heater core and hoses. Is That bypass valve right there where u connect both hoses on firewall.
Anyone got any pics on this? I just might reconsider and fix mine. 95ti

[bucksworld]

Originally Posted by 1996 328ti

Two problems.
One it could be a loose cable to the temp knob in the dash. You would need to remove the glove box and knee bolster. Pop the cable back on and secure it witha small screw so it doesn't happen again. There is actually a BMW bulletin on it.
Two it could be your bypass valve. It's located near the firewall. It's much easier to replace than taking apart the dash. I think you should be able to feel warm water going through one of the hoses if it's working.

When I had my car in a couple years ago, the tech took apart the dash and added the screw. The cable did not pop off though. He then replaced the bypass valve. Now I'm warm and toasty.

My money is on the bypass valve.

Do u have a picture of the heater bypass valve? or diy heater bypass install? anyone? m42 95........