2003 4.6 expedition P0171, P0141 P0138 Rough Idle???

[pdaoaudio]

Hey everyone, Trying to find some info on these codes and how to go about fixing them. I have been rarely driving my truck since my new work commute is 70 miles round trip most days I have been driving my ranger for the majority of the time. The expedition gets driven on bad winter days and my one day a week rest day ( Im a train conductor)

Anyways to the point. I started it up and went to bring it to get it washed and my engine light was on, it have a rough idle while the truck is in drive and you are not moving. when its idling in park it seems to be smooth.

I checked the codes with a a scanner, I have three codes and one my scanner cant read (probably because its just a cheapo) the three i can read are stated in the thread title. po171 po141 po138 .... With that ebing said I notice my rpms kind of hang between shifts and when decelerating along with the rough idle, cant comment on mpg because it isn't driven much and started at least twice a week so keep everything moving but I noticed my power is suffering terribly and is hard to get it to move out of its own way (not that the 4.6 really moves the truck in the first place..... I am really hoping I can repair it on the cheap end which is why I came here to see what the best way to go about this before dumping all kinds of money into it aimlessly.

Thanks in advance guys!!!

Oh and on a side note I have a terrible whine now that changes with engine rpm, sounds like a power steering pump but it doesn't change when turning the wheel so I am suspecting the idler/ tensioner pulley bearings to be shot? Let me know if ya think I am on the right track there

 

[stamp11127]

Here is a good link for code definitions:

OBD-Codes OBD-II Trouble Codes - DTC Codes Car Repair

p0171 System Too Lean (Bank 1)

p0141 O2 Sensor Heater Circuit Malfunction (Bank 1, Sensor 2)

p0138 O2 Oxygen Sensor Circuit High Voltage (Bank1, Sensor2)

What is your skill level? That info helps to tailor future responses to the problems.

 

[pdaoaudio]

Im no mastertech but I can correct any issues myself or with minimal help from a mechanic friend of mine.

 

[pdaoaudio]

My bet is a vacuum leak. I noticed i get a release of pressure noise when the engine is shut off, I will have to further find out exactly where that noise is coming from. I will update that tomorrow after work.

Im going to start with the basics, check the fuel filter, clean the MAF sensor and see what comes up, then Ill then look into o2 sensors.

 

[pdaoaudio]

Ok well today I started to poke around the truck today.... 6 degrees out with about -20f wind chill..... to say the least I am frozen and not very happy.

I got to the bottom of my whining noise. I replaced my idler pulleys and away my whine went!

Come to my surprise when I was taking off my belt I noticed the bottom driver side alternator bolt looked to be as if it backed out, turns out the bolt is sheared right off in the threads. Doesn't look as if I can get an easy out bit on it from the angle, I tinkered around for a while and have given up. there is a small amount of the bolt poking out of the back side of where the threads are and tried to get some needle nose vice grips on it and tried to use some pb blaster on it to get it free but no luck. doesn't even budge, even got a propane torch on it and nothing..... I really am out of options, I put everything back together just so i don't lose anything, I really don't want to drive it with only one bottom bolt holding my alternator in place. any suggestions??????


Now I tried to poke around looking for any worn out vacuum lines and noticed two elbows that seem to be pretty well dray rotted..... on is the elbow coming from the pcv line from the drive side valve cover going to a chamber attached to the air intake manifold close to the throttle body.... the other is towards the firewall on coming from the vacuum line coming out of the passenger side valve cover. Does anyone have the two part numbers for both of those elbows? I would like to replace those as I believe that is where my cel is coming from.

I have also taken off my intake and cleaned the MAF sensor before I re installed it.

Does anyone have those two elbow part numbers, I want to order them asap, thank!