I have been trolling the forums for a while but just regestered because I am at a lose and your guys help. I am pull 12 codes and am about to pull my hair out. It is a 2001 f15 with a 4.2 and 202000 miles. Here are the codes im pulling
P0340 CAMSHAFT SNESOR POSITION A CIRCUIT BANK 1 OR SINGLE SENSOR
P0443 EVAP EMISSION SYSTE, PURGE CONTROL VALVE CIRCUIT
P1451 EVAP EMISSION SYSTEM VEN CONTROL VALVE CIRCUIT MALFUNCTION
P0135 O2 SENSOR HEATER BANK 1 SENSOR 1
P0141 O2 SENSOR SENSOR HEATER CIRCUIT BANK 1 SENSOR 2
P0155 O2 SENSOR HEATER BANK 2 SENSOR 1
P0161 O2 SENSOR HEATER CIRCUIT BANK 2 SENSOR 2
P1401 DPFE CENSOR CIRCUIT HIGH VOLT
P1409 ELECTRIC VACUUM REGULATOR CONTROL CIRCUIT
P0171 BANK 1 SYSTEM 2 LEAN
P0174 BANK 2 SYSTEM 2 LEAN
P1309 MISFIRE MONITOR MALFUNCTION
So far i have replace the following
changed coil pack
changed plugs
changed plug wires
changed camshaft position sencor (sill pulling code p0340)
changed fuel filter
Need some help as to where to begin.. Should I change the o2 sensors to start or?? Any help would be great.. Thanks in advance!!!

 

At 202,000 miles, how much money & effort are you willing to put into this? All those codes give the impression you are running a house of cards that is about to collapse in a heap. Maybe not.
Has what you have so far done changed any of your codes?
P1401 is at least a specific error code - the DPFE sensor is malfunctioning & needs replacing with a Motorcraft unit. Ford issued a series of TSB's re: defective DPFE's over the years. Accept no substitutes. DPFE replacement should take 5 minutes or less of your time & may not need any tools. I would not be surprised if new error codes appeared after you do this.
Lean error codes are a common problem in this engine. Check everything connecting to your intake manifold for defects, leaks, and cracks. Then, read the following thoroughly: https://sites.google.com/site/fordf1...0171P0174-Fix/ The isolator bolts holding the plastic intake manifold plenum to the metal intake manifold commonly degenerate with time & cause intake manifold leaks. AFAICT, there is no way to diagnose lean conditions caused by defective isolator bolts, just replace them. Replacement of these is straightforward but time-consuming. Read the link I have cited, it gives all the details The IMRC stuff included is probably not relevant to your problem.

 

A properly operated "smoke machine" will show these leaks.