Renault R19 1.8rti at low revolutions

Good friends ...
I have a problem with my Renault 19, it turns out to change the spark plugs and now it works a few revolutions, is it as if it worked in 3 cylinders, what could it be?
I tell you that it is gasoline, and I do not use CNC ...
I have also noticed that when I put the air it goes down much more and it even seems to want to go out ...
I need help ...

Although Senso may seem, you consisted if it does not lose pressure for any changed spark plug, or if the spark plug wires make good contact.