It would be helpful if you provided a little more information, like what
kind of problems you are having with the heat inside the car.  It there too
little heat?  No heat?  Too much heat?

When you say that the hoses don't seem tight, does that mean that they are
loose?

You should check the heater control valve in the engine compartment to see
if it is moving when you move the temperature control on the dash.

Whats the problem? No heat inside via the vents/HVAC?

For a 93, try your local garage first. You'll pay up to double the labour
rate for the same service from a dealer.

Stewart DIBBS

 All simple stuff!  Check to see if the heater valve is letting hot
water through the heater core - do the heater hoses get hot?  

 Does the heater blower fan run?  Try all the speed settings, if the
speed control resistor pack has burned out (cheap part at the dealer)
High speed will be all you have.  This can also be a blown fuse, worn
out fan motor, bad switch in the heater control cluster.

 A known fault in some models is a bad solder joint to the switch in
the heater control cluster.   If you can get the fan to come on for a
few seconds by wiggling the switch, that's the problem - pop the
control cluster out and get a soldering iron.

 Do the damper doors switch to the right positions to send heat out
the floor ducts?  On most Toyotas they are cable operated, others have
vacuum motors or electric motors.  Grab a flashlight, lay on your back
in the passenger-side doorway and stick your head in the passenger
footwell as someone operates the control levers, you'll see and hear
the damper doors operating.

    --<< Bruce >>--