may need to get ur fuel tank cleaned... heres the bulliten from ford.. although it does show diffrent codes your having the same problem...
SERVICE BULLETIN:0322 NHTSA ITEM NUMBER:10002472
MFG Bulletin Date: 20030203
Component: ENGINE AND ENGINE COOLING:ENGINE
Bulletin Summary: STREAMLINED DIAGNOSTIC PROCEDURE FOR VEHICLES WITH MALFUNCTION INDICATOR LAMP (MIL) ON AND DIAGNOSTIC TROUBLE CODES (DTCS) P0401, P0402, P1400 OR P1401, OR RUNS ROUGH, LACKS POWER, SURGE, POOR FUEL ECONOMY, AND THE ABOVE LISTED DTCS WITHOUT
Sig removed. See rules.