Hello All....I am fairly new to this forum soI hope I can get some help on my issue. I have a 1998 E-350 V-10 Trition. My problem is very rough idling on start up and throughout driving. This problem happened overnite, fine one day bad the next.Starting the van is fine the engine will raise but then drop so low it seems like it is going to stall, then raise really quickly and idle high for awhile, then back down again to stall levels. If I drive it, it seems to be okay you can hear a miss every now and then but when you come to a stop or slow down quickly, or turn a corner,then it acts like it wants to stall. I can also hear "air noise" near the doghouse, like its loading up, or air is under compression. I have replaced the IAC valve with no change. Replaced O2 sensors, no change.I checked for leaks with carb cleaner and no change there either. I thought the CAT could be clogged so I disassembled the exhaust pipe right before the CAT and started it, seems to make a very small change, but not enough to have solved the problem. Also smells like raw fuel. Also seem to have "bearing noise" (?) near the lower passenger side of the engine. Bad smog pump, (air pump)???? If I get a smaller belt and route around this would it make a difference??? What size belt would this be??? They dont make a service manual for this, andIam having a VERY difficult time finding info on this V-10. I am getting really desperate for a solution as this is a daily service vehicle. Please help me, I beg you fine folks to point me in the right direction!!! Any help would be greatly appreciated!! Thanks!!

SewerRatt