The engine is not overheating, even after i let the light be on for a few days, gauge is still solid dead center. After testing my old tank overnight in the garage for the smallest of leaks i was unable to get any water to come out. I read somewhere on here that the cap is rated for 2 psi. What im thinking is that my tank is functioning properly and the cap is functioning properly and venting. Or the Steam/fluid coming out of the seam is getting above the seam just under the cap.
That would mean that there is something causing excessive coolant to be in the tank under enough pressure to reach the cap.
Air in system (air expands alot more than fluid)
Some clogged return??
I have tried two ways to bleed the system. One cold, one hot. When cold turn key to pos 2, turn heat all the way up, vent valve near tank, add coolant until bubbles stop. When hot same procedure. Got no bubbles when cold, got about 2 seconds of bubbles when hot.
I really hope that someone else has had this problem and was able to find a solution.
I must add that i am not using BMW coolant until i find a solution. Just occurred to me that maybe the coolant im using has a much lower boiling temp. Any thoughts.
Last edited by florida2002m3; 03-19-2010 at 09:34 AM.