1997 Acura Integra low MGP

I have a problem and really need help I have a honda civic 1993 with a b18b1 from an acura integra 1997 ok I just got the pistons fixed because it was throwing a lot of smoke from the exhuast and I just started driving it I filled up the gas tank and it wasted gas like if it was a v6 or v8 I got the car because I wanted a gas saver I did the thing where I read the check engine light codes and my map and tp sensor came up I want to kno if that is causing it to waste gas or any other idea that would make my car waste gas thanks