Heating problems in 20-30 degree weather.

[Engz]

I have been having an issue with my heating and I've tried to research on the issue but couldn't really come up with any solutions. Hopefully I can get someone here that has gotten the same problem.

Here's what happens:

~ First I warmed up the X5 for 10mins and left the heat at 90 degrees (full blast). I waited til the temp gauge needle was at center.
- Around this time, the vent was still throwing out cold air (felt like the AC was on)

~ Drove about 3 miles and still cold air coming out til I got on the highway then I start to feel the hot air coming out.

~ I exited and had to go threw stop lights. Everytime I had to stop, it would start blowing cold air.

** So what I realize was that, when I'm not on always on the gas and I'm at a stop, the cold would come in. And when I'm consistently driving, it starts to heat up.

*** I changed my thermostat before winter hit. Brand new from the dealers.

What else could be the issue?

Thanks

[m5james]

You got a pocket of air, so are both low on coolant AND you need to rebleed the system. There are great bleeding writeups on e38.org BMW 7-series information and links.

[mrbmwx5]

final stage resistor failure

[m5james]

Its not the FSR as that causes erratic blower functions. Since its cold while sitting still then warms while moving, that means there isn't enough coolant in there to move it around properly. This can cause headgasket issues since water isn't flowing completely through the engine, so it needs to be remedied asap.

[Engz]

You two are the man...

I bet it is my coolant. I had issues with coolant level lately because one of the plastic tubes by the reservoir cracked and leaked. I had it replaced.

I'll bleed the system asap.

[m5james]

No problem. Just have some extra Zerez G05 or BMW coolant and distilled water around cause if you're doing it right, she's gonna be messy

[sprocket1200]

though you don't tell us which x5 you have, you may be operating the heater wrong as well. our hvac system works like our house. we set it at 70 and leave it there. the X5 decides when to turn on or off to regulate the temperature to this level.

as well, when first starting out, the x5 is smart enough to have the fan on low until the engine is warm enough to deliver warm air. no use having a high fan speed only to increase the windchill. if your friends regularly do this, just reach over and punch them

[Engz]

It's a 2001 4.4i.

Well James hit it on the spot. Even though the coolant looked like it was topped off, there was some air pockets in the system. After bleeding it, I had to pour in some more coolant.

After warming the car up, the heat was working in park which did not in the last couple of days.

:: Thumbs up ::

[m5james]

Originally Posted by sprocket1200

though you don't tell us which x5 you have

I think I've suggested to him before that he fill out a signature, but I'm pretty sure it's a 4.4. The lack of heating systems he's having applies to just about any car though. If it never heated up in the 1st place, then I'd suggest that the thermostat was broken open. Since he said he's replaced the thermostat and the engine reaches temp, the FSR has different symptoms, low coolant was the only thing really left.

[m5james]

Originally Posted by Engz

It's a 2001 4.4i.

Well James hit it on the spot. Even though the coolant looked like it was topped off, there was some air pockets in the system. After bleeding it, I had to pour in some more coolant.

After warming the car up, the heat was working in park which did not in the last couple of days.

:: Thumbs up ::

Glad it worked out for ya bro. Check the coolant level every couple of days for the next week or so just to be sure.