From one day to another i have to put antifreeze in my 1991 honda accord lx?

From one day to another i have to put antifreeze in my 1991 honda accord lx? - 1

Apparently you have a leak, if there's no sign of anti-freeze on the ground below the engine and no steam coming out when hot then it may be a head gasket leak.

Quite a common occurrence in a 26 year old car. Do you know what a radiator, or mechanic shop are for?

There are two frequent causes that are hard to find: look for a crack running across the top of the radiator underneath the support bar between the radiator neck and the reservoir. There's a flat spot there that loves to crack and repair requires replacing the radiator. Any radiator leak will leave white residue at the bottom on the rear of the radiator… Peek down past the fans with a flashlight. Also look at the edge of the engine from the left front wheel well when you park it. If the water pump is going to leak you will see droplets coming out of a nearly invisible weep hole there.

Otherwise, I fear CB is right about the head gasket. That is easy to screen for. With the engine cool, remove the radiator cap and start the engine. Pinch closed the hose between the radiator neck with your left hand and place the palm of your right hand over the radiator neck, where the cap was. If you feel steady pressure rise within five seconds the head gasket is bad.

One of the signs the head gasket has gone, remove the oil filler cap, if there's emulsified oil (greys colored sludge) on the inside of the cap. I have known the fuel injector seals to fail. Just one point I assume you are mixing the anti freeze with water. If the water pump seal has gone you can check this by removing the cam/serpentine belt cover. Do not remove the cam belt unless you know how to replace it.