M50 Heating Issue.

[E36Ray]

So recently I discovered my car has no heat. At Idle it blows cold when the car is fully warmed up. At City speeds it still blows cold. The only time I get some heat is if i get the RPMS above 3500 RPM by either reving it at idle or when im on the highway. Thinking it may be a bad water pump ? Also the radiator hoses dont seem to be building complete pressure. Hoses seem a little soft not firm how it should usually be warmed up. Did bleed the system but that helped for maybe 15 minutes then back to normal. All help will be appreciated thanks.

[Eric93se]

Has the needle ever crept above the 12 o'clock position? If it has then you need a new water pump. With no heat you either have an air pocket or the heater valve is bad. They now seller brand new aftermarket valves for little money on ebay. If you have an air pocket then you also have a leak somewhere and you have to find it otherwise you may overheat and warp the head. Its also possible that the thermostat has failed in the failsafe open position.

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The M50 has a notorious spot where it can leak coolant, the back of the head there is a fitting where the gasket fails, there is an upgraded aluminum pipe fitting available.

[E36Ray]

There is a small leak i have used cardboard to locate it and seems to be from the expansion tank area but everything seems dry maybe the bottom of the expansion tank? Will figure out leak and try to bleed again.

[enf1945]

broken cable in the hot / cold . . . red / blue spinner ??