Compression issues

Hi,

A few weeks ago the car was really jerking when I drove. The radiator hose was leaking. Replaced hose and clamps. The car sat about a week and whenever it does it sometimes effects the spark plugs. Replaced spark plugs, distributor cap and rotor. Still shaking and temperature is up on radiator still.

Took it in today mechanic. He replaced the thermostat ( temp is still up a 1/4 of the way) and did compression test 1, 2, 4 are at 160 3 is at 140. He says car is on last leg. I find this hard to believe as before the radiator hose went the car was driving fine.

I'm taking it in for another opinion they are going to look at valves and see if they are too tight and check the head gasket.

Anyone have any ideas of what this could be or is the car ready to die? I don't know much about cars, but it's just shocking to me what happened. Sometimes if it had issues with spark plugs it causes it to ride rough but we fixed that.

Thanks!