Heater blowing cold air in my 1994 toyota corrolla gauge goes up then back down

SOURCE: 1994 toyota pickup heater stopped working

Sounds like there is air in the cooling system causing the engine not to overheat but the heater not to work. Flush cooling system and work the air out of the system.

SOURCE: 1994 toyota paseo: overdrive problem

does it loose heat when you set still? is it full of coolent? whats the climent like were you at? is trans. low on fluid?when was the last time trans. was serviced? i know on most cars and trucks low fluid or old fluid can cause it to do what your saying, and also cold weather. some cars have a temp.sensor that won't let it shift into overdrive until car gets to a certain temp. with your temp. guage fluctuating the two could be related. has your service engine light ever come on and then went out, when it did this? if it ever has, have it scaned and see what codes show up. it might be that temp sensor i talked about. well thats the best i can do for you RON hope it helps or at least point you in the right direction to cure your problem. OLD SCHOOL.

SOURCE: how to change tail light brake switch on 1994 toyota corrolla

Normally this is caused by a problem with the brake light switch. If you don't take care of this soon you will have a dead battery, so try this. Look under the dash at the brake pedal. There will be a switch mounted on the backside of the pedal/arm that has a push button switch inside. Have someone stand behind the car and check to see if the brake lights go off when you pull the brake pedal away from the switch toward the driver's seat. If they do, then you need to turn the outer housing of the switch a little bit to make it pull away from the brake pedal when the pedal is in its resting position.

Sorry, I can't remember which way to tell you to turn it but a few turns should be all that it takes. If that doesn't work then you may need to replace the switch but they rarely fail.

SOURCE: leaks on inside Toyota Corrolla on the passenger side

It could be water condensing from the A/C and dripping onto the passenger rug. Check under the passenger side dashboard, above the footwell, for the drain pipe from the A/C. If it's loose the water may leak into the footwell when the A/C is running. Should be reasonably easy to fix.

SOURCE: 1990 toyota corolla wagon 1.6 liter 5 spd. overheating

you've got a possible blockage in the head or block.