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Discussion Starter · #1 ·
Hi guys, and a very merry christmas (belated) to you all :D

Recently i have been experiencing a problem where the low level coolant light comes on, but not all the time?!? I first noticed it when cruising home from work one day. It came on after about 10 minutes of driving and stayed on al the way down the motorway until i came off onto an a road at which point it went out. I let the car cool down and checked the level and its perfect. This problem continues to happen and each time i check the level it is fine. Temperature gauge reads half way once warmed up (in about 3 minutes) so i guess the stat is working okay, which leaves me to think its an electrical sensor?!?


Ha anyone got an idea on ho to best investigate this fault?

Cheers Russ
 

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I had a prob with my coolant level warning turned out to be a faulty cap on my expansion tank only cost £10 from BMW. Prob not the same though as mine was leaking water all over the shop on random days and would show fine on others. Have you had your coolant changed recently could it poss be an airlock or something along those lines?
cheers Si
 

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Discussion Starter · #4 ·
Thanks chaps. I've not had any work done on the coolant system so dont think it will be an airlock. Hopefully a sensor expert will come long soon ;-) and tell me where the faulty sensor is, and that it is faulty!

Cheers
 

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Discussion Starter · #6 ·
Thanks chaps.

So it looks like when i change this i have to drain the coolant, so does anyone have a guide on bleeding up system afterwards please? I'm guessing there are no special requirements other than heater to hot, bleed screws open, wait till air out, close bleed screws, run up to temp, cool down and check?
Only reason i ask is i had an mgf (well the wife did), which needed vacuum bleeding.

Thnaks again gents
 

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1.Jack the front of the vehicle up onto stands as high as possible,
2.Turn the ignition on,engine off,heater on fan setting 1 and temperature fully hot,
3.Remove the rad cap/expansion cap,remove the bleed screw from the rad and IF you have them the bleed screw(s) from the thermostat housing/top hose, return pipe or EGR thermostat.
4.Fill the radiator up and keep pouring till there are no more air bubbles coming out from the bleeds, when good then install bleeds and tighten down(don't snap them),ensure the rubber O-rings/seals are still on the screws/on the bleed holes.
5.Suck some water out so it's not full to the brim, replace the cap and then start the car. Run her up and check for heat from the vents when warm and check if over heating still persists.
6.If good then check the water level again in the morning when cool.
 

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Discussion Starter · #8 ·
So following on from the coolant light intermitant fault, yesterday i noticed the coolant temp was higher on the guage than normal. I let the car cool down and checked the level which was low so i topped it up but it is now losing water.
Its not boiled up and has only just happened but it looks like there might be a leak from the top of the expansion tank.
Ive seen a few other threads stating that the expansion tank is a weak point and wonder if this true?
Can anyone tell me if this is a real common fault?

Thanks in advance

Russ
 
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