A/C & Heat Not blowing...Help Diagnosing

[pdmjr1]

Ever since I bought my E30 the heat has been problematic, but about a month ago it stopped working all together.

Originally, last winter, it just ran weak (it hardly ran at all on the I & II settings) and cut out intermittently from time to time.

Then it started making some noisey racket when it ran as well... and now the fan has stopped working altogether for Heat and A/C. I've got winter coming (in Wisconsin) and really need the heat to work.

How do I start diagnosing this issue? Best guesses?

[Das Delfin]

first would be use google to search

second wold be you rheater resistor

third would be your heater blower

[ELVA164]

Sounds like a bad motor to me. You should pull the cover and take a look, see if it's loose and if it spins freely.

[jhaurimn]

Sounds like your blower motor went bad and eventually seized. Honestly, I would buy a used working blower motor and a new resistor and replace both. Its really not that bad, you just need to be careful putting the new motor back in. Be patient

[JIM1inWisconsin]

blower

Research and pay particular attention to how the metal clamp over the blower goes back in place. It's easy once you know what to do and impossible if you do not.

[7pilot]

1, check the coolant level.
If it is low, heat will be weak.
2, would be wise to flush the coolant circuit.
It sounds like the heater core may be clogged.
3, think about changing the thermostat.
4,When replacing the blower, bear in mind that the motor "indexes" into a notch in the mounting bracket.
If it is not indexed, you'll have trouble with the locking clamp.

m

[pdmjr1]

1, check the coolant level.
If it is low, heat will be weak.
2, would be wise to flush the coolant circuit.
It sounds like the heater core may be clogged.
3, think about changing the thermostat.
4,When replacing the blower, bear in mind that the motor "indexes" into a notch in the mounting bracket.
If it is not indexed, you'll have trouble with the locking clamp.

m

already flushed coolant maybe a month ago, I'm filled up and properly bled...
also Ive seen these little plastic clamp like things in pictures, are those clamps? do I need to worry about snapping those in the cold? should i order replacements along with a blower motor

[ELVA164]

Do some research on this, but I'm pretty sure the Z3 blower motor is the same, but costs less. There's nothing in your original post to suggest anything is wrong with the heater core/coolant system, so I wouldn't worry about that.

[Das Delfin]

there is only a big metal clamp holding the motor in. You have to use a long standard screw driver to pop it out. Look up on the top of the clamp and you'll see how its held in place. Kind of a bitch to get off. When you put the new motor back in make sure it's in the right orientation. It's a subtle click back in place. The clamp won't go back on if the motor isn't in the right place.

def replace your resistor since it's only $20 for our cars. Your initial problem with speeds 1 and 2 going in and out was the resistor but now both are gone.

[ELVA164]

def replace your resistor since it's only $20 for our cars. Your initial problem with speeds 1 and 2 going in and out was the resistor but now both are gone.

Pretty sure the sticky motor was causing that, as a bad resistor would completely stop the blower working anywhere but 4. That said, I agree it should be replaced.

[Das Delfin]

no with bad resistors typically you will see the speeds fail one at a time. For example first one, then 2 etc

[MR E30 325is]

no with bad resistors typically you will see the speeds fail one at a time. For example first one, then 2 etc

This is the exact opposite of what I have experienced. I have to agree with Elva on this one, though replacing a 20 dollar part that may be bad is never a bad idea. Though I wouldn't expect it to solve the issue.

[Das Delfin]

^ I've experienced it in the way I described but the resistor is essentially three smaller resistors set in line and tapped for the different speeds, so if the final resistor in the group fails before the first two then the only speed that ends up working is 4. So I can see how it would have failed that way for you.

Either way it's definitely bad. When my other car went out the resistor was $50. $20 for our cars? I'm jump on that.

[jeffnhiscars]

I think I paid $22 for my OEM resistor so I can see $50 from the dealer.

[Boris3]

I'm near Milwaukee as well. Not a good time to be without heat. Like other folks have said check/pull your blower motor, at a minimum to see if it's turning smoothly and your bearings aren't seized or something is stuck (broken plastic fan blades, dead critters or...). Easy to do with the DIY threads here. While you've got the blower housing opened up you can pull and check the condition of the resistor (both the blower speed springs and the safety switch on the bottom). 1996-99 Z3 blower is the same part # as the e30 blower. Price point is often the same if your buying new from vendors but it opens up the range of your used part search.