Drive ability issues with odII codes
 

I have been a member on here for a while and i recently lost my 2003 ford ranger. I kept with the ford product though. I have a 1999 Ford Explorer 4.0 OHV. since i know this forum is great and the vehicles are closely the same i want to get your help.

I was getting code p0340, CPM.
I replaced the sensor a couple of times and still get code p0340 along with codes: P0135, p1152, p0172, p0175. I think the code p0340 is causing the other codes, but im not sure how to fix p0340 since i replaced the cpm three times and still get the code! is this more a wiring issue or is the PCM-computer the issue?
Im getting real bad gas mileage and and the exhaust smells like gas.
1999 ford explorer 4.0 OHV 2wd.