Weak heater...car also takes a LONG time to warm up.

[Denton]

Hey boys and girls,

My 525i that I've had since the beginning of fall takes forever to warm up. I'm talking 25 minutes for the water temp to reach the middle, driving on surface streets.

Once warm, the heater is very weak. Not only is there not much air being blown, but the heat doesn't feel, well, HOT. I know that I do have the controls adjusted correctly. The "4" setting on the blower feels like what "2" should blow, but is very loud.

I'm thinking that the microfilters need to be changed, but surely there is another problem with the car.

Thanks for any and all advice.

[stilljester]

Have you replaced the thermostat?
If the blower speed isn't proper have tested the resistor?

[Denton]

Have you replaced the thermostat?
If the blower speed isn't proper have tested the resistor?

The thermostat was replaced by a new OE one by the PO at around 75k miles.

The blower speed increases like it should, but when it's on "1" you can hardly feel a thing through the vents.

Have not tested the resistor...so these symptoms are similar to a bad resistor?

[stilljester]

The thermostat was replaced by a new OE one by the PO at around 75k miles.

The blower speed increases like it should, but when it's on "1" you can hardly feel a thing through the vents.

Have not tested the resistor...so these symptoms are similar to a bad resistor?

Yeah mine was just like that - setting on "1" felt like nothing a "4" was basically "2-3"

It take longer to order the part then to install it.

[colo525i]

fan may be part of the problem but the car shouldn't take that long to heat up. I might need a few miles to get full temp even on a really cold night. I'd try a new thermostat while you're at it. They like to pop apart, that's how mine was when i got it out.

[Denton]

Hmmm...thanks for the responses.

So maybe my thermostat just takes a long time to open up? (Not really sure how it works).

It NEVER gets hot, and the water temp will be dead in the middle, but it just takes 20 minutes to get there, and the heat isn't really hot.

Thanks again, and those PNs are very helpful.

[Derek A.]

I have the same problem.

I know my car doesn't have the microfilter and I just cleaned up the heater core.

My thoughts tend to drift toward the blend doors. As I have decent heat but nothing coming out of my feet.

[gtopaul]

Hmmm...thanks for the responses.

So maybe my thermostat just takes a long time to open up? (Not really sure how it works).

It NEVER gets hot, and the water temp will be dead in the middle, but it just takes 20 minutes to get there, and the heat isn't really hot.

Thanks again, and those PNs are very helpful.

You can tell for sure if it's the thermostat by CAREFULLY touching the lower radiator hose after about 10 minutes of warming up. That hose should be damn hot and if you can grab it and hold on (not hot) you've either got a bad thermostat or water pump impeller has come apart.

Paul

[Denton]

Thanks.

Paul: I promise I won't sue you if I burn myself.

[gtopaul]

Thanks.

Paul: I promise I won't sue you if I burn myself.

I appreciate that. I do this test almost everyday on the service isle at work (Bimmer place).

Paul