RPM so low whenever I start my car. Help Please!

Does anyone what is the problem my RPM always below 1000 when I attemp to start my car? Usually, it will go over 1000 when you start the car, after warm up it will go down to normal idel (750rpm). If the weather is cool, my car won't start until I push a gas for few seconds.
When I drive for a while, and restar my car, the RPM never go over 1000 in the cold weather.
When it is hot, it is same problem but I don't have to push a gas any more.
Anyone have an idea? 88 civic 1.5 3door

your throttle cable could need adjustment, or the Throttle Posistion Sensor, or even your fuel pump/injectors can be causing this problem.

Thanks to reply me!
My enging light was on. It was code 7 (Throttle Posistion Sensor). I finally fixed that. I just adjusted the idel a little bit high to around 800-900rpm. It won't have engin light on any more.
I tried to adjust the throttle cable before. It still have low RPM when I start my car.
My car's idel sometime a little bit high (1100rpm)when it hot weather. If i turn on either fan or head light on, it will drop it to normal idel.
I am thinking it may a EACV, or fuel pump can causes this problem. Or my Throttle Posistion Sensor still have problem.

How about charcoal canister?
I found out that was't have any fuel in the charcoal canister. Suppose the 2-way value connect to charcoal canister and output to around throttle body. When purge cut off solenoid value is vacuum, the charcoal canister will transfer some fuel to the throttle body, is it right?

not really sure about the canister thing, sorry. when you first turn on the car 1000-1500 is normal for startup each morning, and every time you put an acessory on(lights etc) the rpms will drop as your putting a load on the engine.

even if it is hot outside, the engine is still cold, regardless, so i dont think the heat as anything to do with it.