Honda Repair: Heater goes on and off, radiator cap, air pockets

Question
What should I look for to solve the problem of my heater going on and off on my 1989 Accord Lxi.  On a recent trip I drove for two or three hours with no heat and then all of a sudden it came on.  After stopping for fuel I started up the car, no heater.  I had to start it several times and then the heater worked.  Any ideas?

Answer
The first thing you should look at is the thermostat. If you have a faulty thermostat, it will affect your heat. You also need to make sure the engine isn't leaking any coolant which would create air pockets in the motor & affect the heat. Also, replace the radiator cap. They are very inexpensive & if it hasn't been replaced in a while, I'm sure it is worn out. Hope this helps