ideas?...strange low coolant problem 2006 530i
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Hi guys, got had a few weeks ago the warning light come on for low coolant, so I opened the cap and indeed it was low. Topped it up with 3/4 of a small bottle of coolant and drove to my garage (not BMW). They pressure tested it for 5 hours and the sensor stayed exactly where it should. No leaks were found. So, I drove it home (about 30 minutes) and didn't use it for a week. Got in this morning and warning light came on again. Opened the cap and it had sunk again! another 1/4 small bottle needed! Any thoughts?
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I don't believe in magic, so I'd get a second opinion from a different mechanic if I was you.
It is probably a very small leak somewhere and it somehow does not show up during pressure testing.
It is probably a very small leak somewhere and it somehow does not show up during pressure testing.
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My Ride: 2006 525XI, Jet black on Dakota beige. Premium and winter packages. I consider myself a purist and intend to keep my car absolutely stock and shiny.
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I second what V said.
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I guess it will be harder to find if the pressure test didn't show up any leak. Maybe sitting at the garage for a few days with paper underneath might shed some light?
Really annoying as I can't trust the car at the moment.
Really annoying as I can't trust the car at the moment.
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Hope its not your problem, but don't rule out a leaky head gasket, it often won't show up on a pressure test and coolant either gets blown thru the combustion of the engine if leaks internal, or evaporates quickly on a hot block or exaust manifold if external.
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If there was an air pocket in the system, the top up might not have been all it needed, driving it could have caused the top up to fill the air pocket, so showing it low again. I would drive it and see what happens.
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Originally Posted by gary8665' post='1091351' date='Jan 15 2010, 01:35 PM
Hope its not your problem, but don't rule out a leaky head gasket, it often won't show up on a pressure test and coolant either gets blown thru the combustion of the engine if leaks internal, or evaporates quickly on a hot block or exaust manifold if external.
wouldn't think it was that. Its only done 27000 miles. taking to the garage for more testing!
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Problem has been found. It was a ring inside one of the pipes coming from the radiator which was worn. The mechanic said it was very hard to find!
Another pressure test finally found it.
Thank god it wasn't something more severe!!!!!
Can't wait to get it back:-)
Another pressure test finally found it.
Thank god it wasn't something more severe!!!!!
Can't wait to get it back:-)
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My Ride: 2006 525XI, Jet black on Dakota beige. Premium and winter packages. I consider myself a purist and intend to keep my car absolutely stock and shiny.
2008 328I Convertible, Sapphire black on beige interior. Premium package, NAV, iPod adapter.
Retired: 2002 325I, Titanium silver on black leather. Premium package. Absolutely stock and proud of it.
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Originally Posted by Dutch 530i' post='1094060' date='Jan 20 2010, 11:07 AM
Problem has been found. It was a ring inside one of the pipes coming from the radiator which was worn. The mechanic said it was very hard to find!
Another pressure test finally found it.
Thank god it wasn't something more severe!!!!!
Can't wait to get it back:-)
Another pressure test finally found it.
Thank god it wasn't something more severe!!!!!
Can't wait to get it back:-)