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Discussion Starter · #1 ·
My car is a 1999 E46 328i and I've only noticed recently that since my last service the Temp gauge hasn't been hitting the "12 o'clock" position on the temperature gauge any more, more often than not lying within the blue bar even after a good twenty minutes driving.
On top of this the cabin no longer heats up as quickly as it used too.. I can have the heater set to 25 degrees and it never really feels as warm as that even after 30 minutes or so driving.
I have also had to top the engine coolant levels up twice in the past three months.


Having browsed the forums a bit, I'm beginning to think it's either a coolant airlock/leak or faulty thermostat.
Am i way of the mark here or does anyone have some suggestions?
 

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99.9% sure it's ur thermostat - as it is in the open position allowing coolant to flush into the rad without warming ur engine block up first. When engine block warms up - the heater core takes the fluid from this and circulates it to the cabin heating functions.
 

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Discussion Starter · #4 ·
If you stop does the temp bar move further?
Nope, it never leaves the first sector of the temp gauge.
I bought a new thermostat today and I'll look into fitting it tomorrow while i'm off work, hopefully it will sort the problem out.
 

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Bleeding cooling system....

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 · #13 ·
The plot thickens!
Had the thermo replaced today, thats sorted the cabin heat and temp gauge problems, but the Mechanic noticed my radiator is fubar'd so i got a new radiator on order now..will hopefully come on friday
 
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