Am i worrying over nothing - coolant message.

[e34.535i.sport]

Ok so im super paranoid over head gaskets, but here's the situation:

I get out the car earlier after a short journey and the coolant level message comes on. I take the cap off and look at the coolant. Its always been a very illuminous green colour since i got it but only really looked at it twice! Same colour with a very small brown swirl in the middle - and i mean VERY small. Also the tiniest ever bit of slidge on the cap (absoltely minute). Even so I'm worrying about it and hoping it isn't oil. I also checked the oil dipstick and all is normal there, changed it about 1k ago and still looks new. So i top up the coolant with a little water (as the shops were shut for coolant), and everything seems fine. Drive for another 4mile and get home wait for a while take cap off, look in the coolant and nothing there- just green. The message has gone away too.

I'm contributing the coolant loss to my driving being a little to harsh the other day when i gave it a good caining, which i dont normally do. My old e46 always used to use a little coolant when i would drive it roughly (I never redline either however).

Any advice or insights greatly appreciated as i'm freaking out here. Please help.

[whiskychaser]

Never had low coolant message except when I drained the rad and block. Think you are in a soft water area so tap water should be OK for now. You got to do the obvious-check for leaks first. Check the hoses and see if you have any drips on the sump guard. Look for mayo under the oil filler cap but that can also mean its running cold. You can have the cooling system tested but I'd be doing a compression test first. To be honest, if your coolant looked black I'd def be worried but not with the tiniest bit of gunge in it.

[ThoreauHD]

I had the same issue but it was from what seems to be a systemic factory issue of the lip of the radiator not being notched properly/gets broke. The hose kept slippin off and some fluid dripped out. I replaced the radiator and all hoses. Although extreme, it certainly solved the problem better than duct tape and a prayer. Just give the hoses a perusal. It's probably just as simple as that, unless you have a pinhole leak in the radiator itself. Good luck sir.

[Paul in NZ]

i have a very slow leak too,i think it is the heater core,cos i get a coolant smell when I first use the heater for a while.One time i did get a mesage a few times in a row i discovered a leak froma hose.A torch and low light really lights the green coolant up,so you can maybe spot a leak.Mine was the short hose that goes from the block to the thermostat....No clue except for a smal pol of coolant sitting in a depression further down

[Karl]

Sneaky leak--if the pressure cap isn't sealing tight it can let a little steam out under pressure and you'll never find it.

A little bit of stuff in the coolant is usually no big deal. It can pick up a little brown/red rust from just age. If it's a head gasket you would have pretty fast loss of coolant, serious oil/coolant mix, overheating.

I did get low coolant message from failure of the coolant level sensor. Mechanic says it's a common thing.

[Rick L]

I had a small amount of coolant leak from bleeder screw. I replaced it and all is good now.

[gale]

Keep an eye on the coolant level until you find a definitive cause of the leak (if that's what it is). The engineers somehow designed the "Low Coolant" message so that it does not come on until AFTER you turn the key off, so if you're on a long trip and start losing coolant, you will only be able to tell from the temperature gauge or steam coming out from under the hood. If you were to have an actual coolant loss while driving and don't keep an eye on the gauge periodically, it will eventually warn you with a chime and overheat message if the needle makes it to the red zone, but the "Low Coolant" message won't display while it's still running. Go figure???

[tdgard]

I had a small amount of coolant leak from bleeder screw. I replaced it and all is good now.

I always have a spare one of these hanging around. It's failed twice on my 5 and once on my 3. The dealer is just far enough away that I can't make it without. Cheap plastic crap.

[whiskychaser]

I always have a spare one of these hanging around. It's failed twice on my 5 and once on my 3. The dealer is just far enough away that I can't make it without. Cheap plastic crap.

Broke the screw on my lady's 3 series and it cost me a new rad! Mine is stuck too and I'm not even going to try and shift it. Think somebody with an evil sense of humour is putting superglue on them

[e34.535i.sport]

Since i topped it up i haven't driven the car too harshly as i've been a bit afraid to put the hammer down (saving me some fuel though!) - but no problems since and no coolant light... I'm hoping it stays that way...