any help is appreciated and i am sure everyone is tired of reading overheating issues on the 2002s - but i think i have a combination of strange things happening.

i have a 2002 cooper with 45,000 miles. no major issues so far (i probably just hexed that.)

secondly, i live on a remote island in hawaii - the island of kauai - and there are no mini-certified mechanics on this island, and i really don't want to ship my car to oahu. but i do have a great general mechanic, so basically i'm looking for some info on where to start and i can pass it along to ray (the mechanic).

in the past year, a few times while idling for long periods, the car has overheated. i heard NO fans come on. shut off the car, let it sit, it cooled down, and i went on my way.

here's the "however" and the other things i'm not sure are related -

1) most of the time, the fans do come on when they are supposed to and the car doesn't overheat. that's good. but once they come on, they go on and off in really short cycles, less than 2 minutes usually, even on cooler days. which makes me think the car is running hot, but not quite overheating...?

2) the a/c fans work. (more on the fans below) (the a/c is never cold, though, so that part probably just needs a boost)

3) i can hear the whirring sound coming from the PS - is that the fan or the motor? i've found posts that say both...

4) when any fans come on - radiator/cooling or a/c - the entire car has a huge very noticable vibration and vibrating sound, which can be heard easily outside the car - i'm not talking about the sound condensers make when the a/c comes on - it's the fans themselves, even when the a/c is not on and it's just the cooling system (but also when it is).

i didn't find any blown fuses but am wondering since it seems intermittent, should i just replace that fuse anyway? (maybe they short out a little or act up when they start to go bad? i'm just a girl )

is any of this related, or do i have separate problems? what should i tell my mechanic to look for?

THANKS! this website has always helped me with my mini questions!!

 

I think I follow what you are describing.

Do you still have the original coolant in the system ?

Was the tank topped off ?

High Speed fan is very loud, vibrations not so sure about. Are any of the fan blades missing pieces which would throw off the balance of their spin ?

 

If you have the correct level of coolant and the engine overheats (occasionally) without the radiator turning on, the possibilities are...

1. The radiator fan has 2 speeds, the LOW speed relay might be faulty.
2. The thermo sensor that activates the fan is faulty.

As for the A/C, that's another beast altogether. You should have it checked separately. Btw, with the hood open, you can hear, feel and see the radiator fan spinning.

 

Since the fan is cycling on and off when it does work....that is a symtom of the resistor failing, disabling the low speed fan. The fact that the fan fails to turn on high sometimes, vibrates a lot....sounds to me like the fan needs to be replaced. Moist salty air I'm sure has played a part corroding it. I would as a first step, swap out the fan. Aftermarket units are $100 or less, and seem as good as the $350 dealer fan. It is also possible, like stated above, that the fan is sometimes not recieving the signal to turn on...so you could have 2 problems, that could most likely be trouble shot with a multi meter to see if the fan is recieving a signal.
The A/c is likely just low, or the compressor worn and not producing pressures needed...your auto guy when he plugs his recharge machine in will be able to tell.
The fact you can hear the ps pump/fan under the car is a good thing...if you have your mechanic blow the dirt out of it, and maybe lube it up, it will ensure continued opperation of it, ensuring a cooler ps pump.
One tip...be careful when you order the new radiator fan...you need the earlier version, as the fan was redesgined to move a relay off the fan, and the 2 units are not interchangable. Of course, it goes without saying, you have already checked you coolant tank for fluid level correct.

 

to all of you guys - THANKS! all of your answers make sense to me.

i bought this car used a little over a year ago. learning it's quirks and addressing them has been an adventure. but i got a great deal and she's worth it.

1) yes, the coolant is topped off, but based on the color (definitely not the neon green of fresh antifreeze) i'm gonna take a leap and say it needs to be replaced.

2) the speed of the fans, regardless of when they come on, seems to be consistent and always loud. i think all of you right that the low-speed isn't kicking in. i'll have my mechanic check it out. the idea that the thermostat could be dying is also a possibility - so we'll check that out, too.

3) the last time we had the car raised to look at the serpentine belt wear (which was very uneven - weird), we checked the fan blades and they were good, and checked the PS fan to make sure it was clear, so that part has been done. but that doesn't mean it wasn't a pre-existing condition.

4) and, we'll look to see if it needs a new fan altogether.

thanks so much guys!!!

 

Keep in mind the original BMW anti-freeze is dark blue, not green or orange.

 

Note that there have been many reports of used original coolant coming out a disgusting looking brown (and I concur.)

 

Brown and chocolate are signs that coolant has mixed with oil, which means the head is warped.

kimi - with regards to the thermostat, I would play it safe and replace it. Thermostat can die slowly once it's exposed to coolant that is above the normal operating temperature.

 

^^ The thermostat could be partily opened & they really die slowly.

 

id say its the thermostat as well, get that checked!

 

02's was notorious for having brown coolant. At one point premature coolant flushes was given to anyone who complained about the odd coolant color.
My advice is take your car to someone who knows what they are doing before you spend money on all the things everyone is suggesting.

 

I don't get your take on the coolant flush. (I have a '06.) What other ways can coolant go brown besides oil leaking into the coolant via a warped head, leaky head gasket and/or a bad oil cooler/heat exchanger? Left-over crap from the machining and/or assembly process? Or is it a special formula BMW is using to morph the color?

And besides going on faith, how does one to know if the advice of a supposedly professional mech is correct unless one know/understand the problem oneself?

Me, I've spent less than $100 at the dealer since 1986.

Lucky I guess.... knock on wood!

 

Anyone who has been around long knows that the 02's had this problem. I work on a lot of mini's and still to this day 02's will roll in with dark coolant with no problems to note with coolant system.

 

also dark blackish can be coolant too old and electrolisys is present .

 

as the coolant picks up metal via corrosion it gets electrically charged . as the charge increases , everything accelerates (vicious cycle) . this is electrolysis . only way to prevent it is to flush regularly . it loves aluminum .