OK guys here is what I got. 2003 Ford Ranger, 3.0L V6. The g/f was drving the truck home and it was barely running. Rough idle and rough driving. Could not get over 60 mph on the interstate. Last night I pulled the following codes:
P0171, P0175, P0300, P0304, P0305, P0306 & P0316. After I pulled the codes I cleared them. Today I went to work on it and let the engine idle. Still rough might I say. CEL
came on and I got these two codes I have gotten before yesterday. P0304 and P0316.
Here is what I tested. I sprayed starter fluid all over the place and got nothing for a vacuum leak. I did and ohm test on the fuel injectors on cylinder 1, 2,3 & 4. Could not get to 5 or 6. They tested within spec. I also listened to hear the tick of the injectors while running and they tick with no problems. I did a resistance test on the coil packs and they were within spec as well. Primary and secondary. I checked the resistance on the plug wires and they were good as well. Pulled the plugs and they were good as well. The reason I say this on the plugs and wires is I replaced them last summer. I also did a fuel system pressure check at the schrader valve and it was running 62PSI with no fluctuations.
I am pretty much at a loss here. I have not ran a compression check yet cause I am finding it hard to believe that be the problem. The g/f has taken pretty good care in making sure the oil is changed and not running the crap out of it.
I really could use some help here. If anyone has any ideas or have ran into these same problems let me know. Thanks!