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Having owned my Z4 for approx six weeks, I'm lovin' every mile I drive it for.

Just wondered............My temperature gauge reads half way all the time. I've been stuck in mega traffic and motorway blasts. Temp gauge never moves from the twelve o'clock position once the engine is at running temp. Is this normal?

The gauge reaches this position from a cold start in the morning within one mile covered. Just wondered if the gauge is/are reliable, etc.

My cooling system has been pressure tested - no leaks.

Cheers for any replies.

Mine does the same , although it takes longer than 1 mile to move to the middle but maybe im taking it easier than you

Nothing to worry about i would say

Ok cheers .............I take it easy on a cold engine. I'm always surprised how quickly the gauge reached half way. No worries though. As long as it doesn't go any further near to the red section.

The gauge definitely works as i've experienced it go into the red! Had to bleed the coplant system as there was air in it. Luckily no damage and it's still going strong 2 years later.

Mine does the same, it does seem to warm up quickly but then I'm used to diesels.

It is the quickest car to warms up I have ever owned .............rock solid at half way no matter how its driven

This is my 4th BMW. The two 3 Series and 2 Z4's have been the same. Needle never goes further than the middle.

Either it's a very good system or the needle doesn't actually go further than halfway on any of the cars and we're all being conned!

An my android odb app it sits around 100 give or take a couple of degrees

My car does the same and boy what a heater, came home from the Ace cafe last night on the M40 with the roof down, nice and cosy

Just remember that's coolant temp, not oil. It will take 5-10 miles for the oil to get up to temperature - and it's the oil that's important in preventing engine wear.

Mine sits below halfway for some reason. I have a new thermostat so it shouldn’t do really, unless something else is wrong. Or the thermostat is faulty. It goes up to halfway if I’m driving around locally especially if I’m giving it a bit of revs but as soon as I’m on the motorway cruising along it drops below halfway.

That sounds normal to me. All my BMWs fitted with temperature gauges sat below half-way on Motorways and only got half-way on hot days, either stuck in traffic or "pressing on"!

Both of you have got faulty thermostats. Since at least the late 80s BMWs have a gauge that doesn't reflect temperature as an absolute but rather a selection of ranges. There is stone cold (blue block), warming up (it will move through an arc here), normal (exactly dead centre), over-heating (think this is a one position point) and stop now your engine is going to explode (illuminated red block). Normal covers something like 80-100C without moving a millimeter off centre. If the needle doesn't sit here when the engine is warmed up or drops back out of it when on the move then the stat is toast.

Ah bugger. To be fair it apparently it is a new stat but it wouldn’t surprise me if it’s knackered anyway. The last owner put radweld/ k seal/ possibly both in the cooling system to cure a leaking hose (numbnut) and I’ve been flushing it out since so maybe it has bollocksed the stat up. I’ve never done this but isn’t it possible to boil them and see if they open and close in a pan of water?

I'm not convinced as I'm on my 5th that sits a bit below half-way.

My current MC is actually oil temperature and has numbers on! It tends to settle at 75 degrees whereas mid-way is 100. And if the thermostat was faulty it wouldn't stop the temperature getting up after over 300 miles!