I have 1995 Honda Civic EX and noticed it started to burn a little more gas than normal. I put a scanner on it, not because I had an engine but just to take a look to see if something was happening that wasn't suppose to. I'm not coming up with a code but the scanner shows the open & closed loop status being closed for about 4 seconds AFTER you rev. it to about 2800 rpm then goes to an open loop and remains there even while road testing. While road testing it may go into the closed loop(sometimes) while decelerating for approx. 4 seconds but will go back to the open loop. It won't stay in the open loop while driving. I've changed the 02 sensor and replaced the ECM with another ECM that was supposed to be good but coming up with the same thing. What else controls the open/closed loop status? Any ideas?

 

maybe a throttle position sensor and a mass air flow censor? Im not too sure.