91 Corsica, No heat, temp gauge max, speedo dead

In the past month these conditions have come up:
No heat - low coolant light comes on
Temperature gauge is always pinned at maximum, as soon as started
Speedometer, odometer do not move
Stalled once and battery was dead - wouldn't turn starter fast enough - a few hours later everything back to normal
Stalls sometimes at lights, when slowing down


These things have recently been done:
Heater core was replaced (cracked pipe connections at hose end)
Fitting that connects rad hose to block on driver's side cracked, and replaced (cracked around threads)
Blower motor replaced

Every time I bleed air out of the system there is heat, and it gradually gets weaker. If left overnight, there's no heat again. I thought I got all the air locks and leaks taken care of. Theres not visible coolant dripping.

Please help

Sounds like several tough problems. I have a 91 also. Low coolant light won't come on unless overflow is low, or pinched. If yours is leaking that of course will cause that. Hard to say where to start, but be sure you have all good hoses, a good thermostat, and watch the engine when warm to see if any fluid is being thrown anywhere. These cars sprout leaks (mine has another one). Sometimes water pump, loose clamps, old hoses, and even intake manifold. I had a problem several years ago where I had a cracked head, which was expensive to fix. Was blowing coolant out the exhaust. May be neccesary to have a shop put in some dye into the cooling system then check with UV light to see, or perhaps a simple pressure test can help. I found a small hose leak with a pressure tester I have but I still have a small one that I will have dye used on later to check.
As far as the guage goes, can try to replace the temperature sending unit on the engine as it is cheap. May be a bad guage too, if it is going up as soon as started. There is a chance your ECM could be causing this, as this is common item to fail as well. If nothing else is goofing up though and car runs OK, then most likely the gauge or sender unit.
One thing more, head gasket problems can pop up on these, especially on 4 cylinders.

I have a 94 that is in the shop right now. I first took it in the shop when the low cooolant light came on and the temp. gauge would max out after about 3 miles. The first time they said they couldn't find anything wrong. Then the next time i took it in they said it was an intake manifold problem, over $700. Still didnt fix it so they replaced the radiator and water pump, still didnt fix it, now they are changing the head gasket, hopefully this will fix it seeing that basically i have a brand new cooling system

It's a blown head gasket in the front. Now it's leaking coolant outside the block too. Dunno if I'll fix it - the car is, well, worthless if you look at it.