Car over heating

Sounds like either a thermostat problem not allowing cooler flow car overheating , fans not cutting in causing over heating , or the real nasty head gasket do a compression test to eliminate head .

is the vehicle having any cooling issues? I.E. overheating? you could have a air pocket and the system needs to be bleed or once vehicle warms up check upper and lower radiator hose to see if one is hot and one is cold they both should be hot if u have proper circulation. did you ever have heat? when did this start do you have any check engine lights

this is most likely a sensor, or starter solenoid. i had this problem with my 1972 monte carlo it was the headers overheating the starter and its wires, i had to arch the starter many times till i install a heat shield,newer cars have heat shields. check to see if your starter wire is too close to engine or exhaust

water level was low thats why it blew cold ,you may have a slight leak somewhere but once the level drops below a critical amount then it will overheat so ask a local mechanic to have a good look for you as this sort of problem is often beyond the scope of a owner to locate the leak ,when running check the difference between the top and bottom rad hoses as well if bottom hose cold then it could be the thermostat .

To troubleshoot this types of problem,click the link below :----http://howtobyme.blogspot.in/2012/02/heater-blows-only-from-defrost.html
--------Go through the procedure to confirm the issue.

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Engine Overheats and heater blowing cold?

http://howtobyme.blogspot.com/2011/11/engine-overheats-and-heater-blowing.html

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Heat blows cold on drivers side and hot on passenger side?

http://schematicsdiagram.blogspot.com/2011/12/heat-blows-cold-on-drivers-side-and-hot.html

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For car running hot and overheating issues, I suggest to you go through this help links. Click this link below and go through the troubleshooting procedure to take care of the problems: ----Car runs hot? http://howtobyme.blogspot.com/2011/11/car-runs-hot-in-traffic.html
-----------All types of car overheating problems and troubleshooting?

http://technoanswers.blogspot.com/2011/11/all-types-of-car-overheating-problems.html
Car freeze overnight and started overheating while driving?http://technoanswers.blogspot.com/2012/01/car-freeze-overnight-and-started.html-----------Engine Overheats and heater blowing cold?

http://howtobyme.blogspot.com/2011/11/engine-overheats-and-heater-blowing.html

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Car overheats and Air blows hot at idle?
http://howtobyme.blogspot.com/2011/11/car-overheats-and-air-blows-hot-at-idle.html
--------overheating? http://schematicsdiagram.blogspot.com/2011/12/buick-century-overheating.html
----------Car engine Overheats and transmission starts slipping?http://schematicsdiagram.blogspot.com/2011/12/car-engine-overheats-and-transmission.html
----------This details will help.Thanks.

is it blowing white smoke out of tailpipe and mixing antifreeze and engine oil if its doing this and overheating you need a head gasket!were is leak coming from were ever it is has to be fixed in order to get heat

stuck thermostat, replace stat

Thermostat needs to be replaced for overheat. If it didn't open, then coolant becomes stagnant then causes engine overheated. Once it was overheated, it destroyed the coolant temp sensor. The signal from this sensor will feed in your ECU to tell it to open your cold start valve to spray extra fuel into engine to assist the start. Replace the Coolant temp sensor for your start problem.

sounds like it might be low on coolant. Low coolant levels will stop the flow and circulation to the heater core, and also might be the cause of overheating

Generally when the heater isn't heating anything and putting out cold air the heater core is bad. I have never worked on a BMW before and have never heard of a heater core causeing overheating, but because they are linked, it maybe a clog in the core causing poor coolant circulation.