over heating, help!

[Maximum_E30]

i just replace the tstat, fan&fanclutch, flushed the coolant system with water, heater blows cold(no heat what so ever) but motor cools down at higher rpms. A lot of pressure builds up in the coolant system as well, enough to leak out of the bleeder on the top of the radiator even when screwed down as tight as possible. im thinking heater control valve but not sure and suggestions guys? any and everything is much appreciated. thank you

[e30construction]

Bleed the system by:

1) Using ramps or a jack get the front of the car 1' or more higher than
the rear. That will make the radiator and bleed screw the highest point
on the engine and facilitate removal of air.

2) With the bleed screw open, add coolant until no more air comes out of
the bleed.

3) Leave the filler cap off, or at least loose, and set the heat for max
temp and fan speed. Leaving the cap loose will prevent air that's still
in the system from causing a "coolant fountain" once the engine heats
up. Start the engine and allow it to warm up to operating temp. As it
warms up occasionally crack the bleed screw to release any air and top
up the coolant as necessary.

4) Once the engine is at temp bring it up to 2000-2500rpm for a few seconds
several times. Then crack the bleed until no more air is released. At
this point the heater should be throwing lots of hot air, which
indicates that the heater core is filled with coolant. You may have to
repeat this a few times to get all the air out.

5) Drive the car a bit, allow it to cool back down, and recheck the
bleed for air. Over the next few days you may get very small amounts (a
few bubbles) of air out of the bleed screw.

[e30construction]

still have air in the system, this is what i did when bleeding these m20

1. jack up front 1-2", then start up the car let it warm up with cap and bleeder closed.
2. Turn on heater high
3. when it warm up, open up the bleeder screw till no more air comes out just liquid, then close
4. open the res. cap and top off coolant
5. Locate the small hose that goes from radiator to res. and lift up the middle of the hose so it's higher then the bleeder screw. You should see bunch of bubbles coming out.
6. r3v idle to 1500-2000 rpm for 5-10 sec
7. Go back out to the engine bay and repeat step #5 till no more bubbles come out, top off coolant as needed.
8. Get in your car, get on the highway and gun it a few times then go home park with uphill incline and repeat #5 again. GL