PLEASE HELP ASAP!!! Check Coolant Level
 

Please excuse my ignorance as I'm definitely not a mechanic. So my check coolant level came on this evening. This happened before about 2 months and I took it into the local BMW dealer to get a top off. As I recall, they just filled it with water. So tonight, I did the same. Now, I seem to recall that they had used distilled water not tap. :(

Question...Did I make a big mistake or am I safe for a day or so? Quick responses are greatly appreciated as I need leave for a 3 hour one way trip in about 6 hours.

You are safe in using tap water to top off. It isn't a long term solution as you need to add coolant (which is 50% water usually) but for a top up it is fine.

The more important question is where is the coolant going. You may have a cracked coolant tank, or another leak. You need to keep an eye on the level, as running low can cause engine damage if it overheats. If it took 2 months to go down, fine, but it may be an idea to put a gallon jug of water in the trunk for your trip. If you have to top if off again get it pressure tested and checked for leaks.

Good luck

Yes, JCL is right. The main thing to look into is where is this coolant going. If you are topping it off very frequently, like once a week or so, then you have a problem and you need to get it checked. It happened with me and i had to replace the valley pan gasket.

In my case the low coolant was indicative of a leak at the water pump.(37K miles!) No matter what it may turn out to be you need to find out where the coolant is going.

:iagree: What's your mileage? the OEM (original equipment manufacturer) water pump has plastic vanes and thus usually fails between 60-80K miles. If you have a 3.0, there is an aftermarket water pump available with stainless steel vanes. No such luck for the 4.4,4.6,4.8 engines. But definitely find out where it's going. It could be as bad as a cracked engine block or meerly a leaking gasket, Either way it's not something to ignore.

Thanks for all your responses. Very much appreciated! X is a 04 4.4i with approx 55K miles. I'm going to take in take for the 60K service pretty soon so I'll be sure to have them check this out.

It's not ideal to use tap water, but you should be OK.