[Stuart]

While driving down the free it will surge and chug. Also from a dead stop when I stomp on the gas it will go, but VERY slugish. The dang thing won't even do a burn-out anymore. for codes this is what we get. 172 and 176 which are for low voltage O2 sensors and Lean Bank 1 and Bank 2. So far this is what we have replaced:

Spark Plugs
MSD Wires
MSD Cap
Rotor
PCV valve
Fuel Filter
Fuel Regulator
Air Filter
Cleaned MAF with electrical cleaner
changed oil and filter
Throttle Position Sensor
A couple bottles of injector cleaner
Both O2 sensors

On top of the fuel regulator there is a hose and we took it off and blocked it. It ran fine after that but when we talked to the Ford Dealer service guys they said not to because the fuel pressure will get up to something like 172psi and you will find fuel in the oil. We ran it like that for about 2 days. No Fuel in oil, but right when I put the hose back on the fuel regulator it ran like crap again. PLEASE HELP!! I have no Idea what it could be now. We have checked most all the sensors with a DMM and all tested ok. This is SOOOOO Frustrating!!!

Could it have something to do with the EGR valve maybe?

Thanks for all your guys help!!!