Engine Problems!!

I have a 2g 97 eclipse 420a motor. I'm getting really bad gas millage and the car will die for a split second when driving. It does it at all different RPM's and speeds. I have replaced the O2's and the spark plugs and the fuel filter and have checked for any arching and any vacuum leaks but haven't found any thing. I did replace the header and the down pipe but that should not be the problem. Any Ideas or more information you need ask and I will give the best info I can thanks.

im having the same problems with my talon and have replaced fuel filter and full tune up. im getting a check engine light with a obd code reading of P1296, i still dont know what this problem could be

Pushin_20s
I used this website: http://codes.rennacs.com/PCodeSelectDetails.php?VehicleMake=Mitsubishi&VehicleSystem=Petrol+Engine&VehicleYear=1996&VehicleRegion=Japanese%2FKorean&FaultCode=P1296&Description=Please+enter+fault+code.%09%09%09&commonRepairs=

P1296 = This Relates to MAP sensor - no voltage supply

Check the wiring that connects to your MAP sensor where your intake is. It could be loose or unplugged. The wires could even be damaged.

Thanks I actually went a head and took off the throttle body and cleaned it then disconnected the battery and the car runs great!