my temp gauge keeps going up and down
 

coolant was low, so i fixed that, but the problems persisting.

whenever i come to a stop, whether heater is on or not, my temp gauge flies up into the red. then, once i get moving, it slowly gets back down to normal again. then as soon as im stopped, goes back up to red. its been doing it for the past 2 days, but now it seems to be getting worse, with it heating up faster at stops. any ideas on what might be causing this?! any help would be appreciated. im going to try and take it into the dealer tomorrow to see if maybe they can find a problem.

another interesting thing is that whenever i turn off the engine, this vacuum sound keeps happening after the motor is off. again, i thought it was a low coolant issue, but im not so sure anymore, since i just put some in and the problem persisted.

Couple things to check...
 

is your radiator fan coming on? I"m guessing not, cause you heat at rest and are fine when moving. Check your fuses.... Also the motor speed module (mounted on the radiator support) isn't the most reliable part on the car... Sad thing is that it's not that cheap to replace.... Maybe you can get the parts from a wrecking yard.

Also, low oil levels will make the temps swing more than normal, but your car sure sounds like the radiator fan isn't working.....

Matt

I had the same problem on my 03 MCS. Turned out to be the water pump!

Coolant level
 

How much coolant was missing? After topping off the coolant did you bleed the system for air in the system? If not, you have a pocket of air that comes into contact with the coolant temp sensor (Hot,cold, hot).

well, i took it in, explained what happened, and basically they said its happened a lot before, took the car away, ad im getting it back tomorrow, all fixed under warranty. cant wait to hear what was up.
in the meantime, i got an r56 im riding around in, and to be honest, im not sure what to make of this car quite yet. def a weird change from the first generation. feels like a corolla in comparison, probably because of the suspension mostly and the "way too loose" steering.

Did you find out what the problem was?

sorry for the late reply, i didn't get a chance due to a business trip to pick up my car until a couple of days ago. as far as the issue, apparently, and surprisingly to me, there was a leak in the coolant tank. they fixed it and for the past two days the car's been running just fine. glad to have my mini back.

Still a relevant problem or not? I think yes. Also still need answers so thanks for not helping.

Well, since the OP is the only person who could answer your question (price of repair to their car), and his/her last post on this forum was June 16th, 2010, you might be in for quite the wait...

the GEN1 S coolant overflow tank is prone to leaks developing at the seam joining the two halves

https://cimg4.ibsrv.net/gimg/www.nor...811e8fd196.jpg
when this happens on the back side - against the firewall - it can be easily overlooked. Watch for signs of coolant drips cooking on the heatshield below . . .

it is neither expensive ($20 approx) or difficult to replace
https://new.minimania.com/part/NME76...2-R53-Cooper-S

I've replaced several for folks over the years including the one in my own 2002-S

there are alumin' replacements which are much more expensive


***************

your problem could also be the classic 'fan resistor pack' problem

as you know the electric fan cycles on and off as needed and has two speeds. Normally only slow speed is needed for most driving ... when the fan pack loses the low speed, it will cycle the fan only at high speed and this can cause the temp to be going up and down while low speed would have been holding temp more constant .... The fan is much louder at high speed. There are many threads on this issue as for a long time the only fix was $$.


********************
p.s. I see this is a first post for you

I'm usually one to jump on a 'resurrection' post myself - reply to a thread that's been dormant for years .....

There ARE valid reasons to ask a follow-on but if they are only answerable by the OP (original poster) consider a PM (personal message) rather than a general post ..... just mentioning in case you don't have much experience on "forums" like this ...... there are 'protocols' :roll: :lol:

altho in this case you probably selected the best path!