[lemonpark]

hey guys,
So, I took my car to Active last week and that day I got a notification on my iDrive saying low coolant and a yellow light/symbol on my dash so I told them about it and they filled it up with coolant.
It was fine until a few days ago and it said low coolant again, I thought it was weird and just topped it up myself once more. After driving my car to a friends house and getting back in a few hours later the message popped up once again and I could see coolant under the car. Took it home and it's been sitting in the garage ever since. I'm pretty sure it's one of the hoses, I talked to a few people on the forum which I met at the E9X meet and 3 of them had the same problem before.

Should I get it towed to a mechanic (Worx or Active) and get them to do a pressure test? or just look under the car and try to look for a broken hose?

[Scotty89]

I wouldn't bother getting it towed for a pressure test.

If you can see coolant from underneath the car - something is wrong. Coolant isn't supposed to come out at all.

I had the same symptoms as above on my e46 - a very slow leak, that only dribbled enough to cause low coolant warnings between top-ups. It turned out to be a hairline crack in my expansion tank.

This part was notorious for its failure on the e46, and it was easy to diagnose. With the engine on and running at temperature, the hairline crack in the plastic tank would spray like a little water pistol.

I have no idea if the same fault occurs in the e92, I doubt it since its a different tank all together. I would try looking around your engine bay while the engine is warm + running, as you will be able to see where it's leaking from.

I would expect that if it's a hose, it would not be a slow leak. Under pressure the hoses I would expect to leak a lot, to the point that you wouldn't be able to drive it without too much loss of coolant.

Depending on the colour of your coolant, you should be able to see where it's leaking from without too much trouble. Mine was red, and dries a bright pink colour, easy to spot on black plastics and rubber.

[NBTBRV8]

Mine turned out to be the top plastic hose that comes out of the head and it was running down the side of the block. It was really hard to diagnose as it would only leak when the car was really hot.

http://www.e90post.com/forums/showthread.php?t=983356

[lemonpark]

turned out to be a cracked water pump which is really rare apparently, mostly they will just fail not crack, I'm still working something out as I think the previous owner had it replaced less than 2 years ago but the receipts are in the car which is at Active. If it was less than 2 years, I already talked to BMW Doncaster and will tow it to them and get it replaced under the parts warranty.

[kau1991]

have car services in a shop in darlinghurst in a very good price but finally found out they put water to my car instead of coolant. Want to report it to fair trading but my friend said it wont works as there no ways to prove they put water in or to prove no one else have changed anything from my car after the services.

Please help.

[naynay]

so what's wrong with your car?

[kau1991]

nothing wrong with my car but i think normally they should put coolant, right?

[naynay]

drain it asap and replace it with the proper stuff.

[jy]

hi, thought of sharing my experience. recently had slow leak. had to top up once in a few months - hardly drives the car. during recent service, i highlighted this to the service advisor. pressure tested and turns out the thermometer is leaking. got it changed and all seems good now. not sure how much it cost exactly. was a long bill, but i think it's circa 200?

[lemonpark]

is that the thermostat?