i have a 94 f150 4x4- 4.9 with 189k on the clock. its got the 5 speed came factory with 308 differential but swapped them out for 355. i thought this mite solve the power problem but it did'nt really help much. i had problem at in town speeds with the truck surging and found out on this site it was the egr valve so i put a plate between the egr and the manofold.. it stopped the surging.. but i cant seem to get more the 10.5 miles a gallon out of it i keep it under 2000rpms unless im at highway speeds at 65 it sits at 2150 with the 355's.... i was thinking it mite be the cataladic convertor. the hose that is in front of the convertor rusted out i think it goes up to the smog pump i tried patching it with fence wire and several layers of jb weld held great for a week until i hauled my camper and truck got pretty hot not overheated i was thinking the converter mite be plugged and making back pressure blowing out the jb weld also i can hear exhause under the hood not from the donuts but from the air pump. the temp gauge never worked so i put a new sensor in it still didnt work so i put in a manual gauge. i heard someone mention that if the temp gauge for the computer is'nt working the engine will run rich. if i put my hand behiond muffler the exhaust gas seems hotter then it should be. i love this truch just wish i coud get better mileage. would blocking egr val;ve make me lose4 power and mileage?? i was thinking of taking exhaust off and punching oput the convertor. any advice????