My search came up empty, so I can use some help here. Apparently my tuner somehow blocks these trouble codes from coming up because reseting the truck to the stock tune for inspection threw the codes P0054 and P0455. Some quick searching got me this:

Check Engine Light Code P0054 - HO2S Heater Resistance (Bank 1, Sensor 2)

Possible causes:
Blown oxygen sensor fuse
Open circuit in oxygen sensor harness
Open circuit internal to oxygen sensor
Open circuit in PCM
Short circuit in oxygen sensor harness
Short circuit internal to oxygen sensor
Short circuit internal to PCM

Check Engine Light Code P0455 - Emission Control System Leak Large

Possible causes:
Loose gas cap
Non conforming gas cap (non-factory)
Other leak in Evap system

I'm not so worried about the P0455, that one is most likely an easy fix. I don't know how to handle the P0054 though. Is this usually the code thrown when it's time to replace the O2 sensors? Does anybody know what the voltage is supposed to be over the O2 sensors and where I can find the fuse(s) for them? I do have a slight misfire, and I'm wondering if it could have something to do with this. I should also mention that the truck has 112,000 miles on it and none of the electrical parts have been changed out other than the spark plugs and wires.

 

I found the fuse locations under the hood for both the PCM and the O2 sensor, neither of them were blown. It looks like the next step is to find some info on how to test the O2 sensor and/or it's wiring harness.

 

Bump.

 

First I'd chase the wiring harness from the O2 back toward the engine looking for any chafing or if it has been against the exhaust. Most likely the heater side is bad in the O2.I can't find the schematics to tell which 2 wires to check resistance are right off ( there's 4 coming off the sensor).
If you changed the clutch recently check around the bell housing for a pinched wire between it and the block , it happens.
The evap leak could be a few things , from a cracked hose or bad cap , to a malfunctioning purge valve.

 

Thanks Ken. The clutch was changed recently, so that's some good information. If the heater side is bad in the O2, does that mean that the O2 sensor has to be changed? I'm not very familiar with these things.

I know we have a few O2 sensors on these trucks, where is this one located?

 

Should be pass side bank 2nd sensor from the engine.
And yes ,if the heater in it is bad you change the sensor. Some sensors have 2 wires (no heater) 4 wire sensors have the heater. You may have both on there so that should help narrow it down.

 

Thanks again Ken, hopefully I'll get to crawl around the truck tonight to have a look at this thing. If I don't find any wires melted to the exhaust, pinched within the bell housing or frayed; is it safe to assume that I need to replace the O2 sensor? I know these aren't cheap, but should I also change out the driver's side sensor at the same time?

 

I'd save the money for when they go bad. Some last 2-3 hundred k miles.
No sense fixing it till it's (or you are ) broke.

Maybe if someone who has schematics could chime in and tell you which wires are for the heater going into the sensor plug , that would help tell if it's the sensor or not , but most likely it is.

 

I went under the truck today and was surprised to my see that my connector for bank 2, sensor 2 was engulfed with oil. Apparently during one of my last oil changes I must have moved the rubber part that protects the oil from coming off the filter and drenching the part.
I took apart the connection for that and blasted it with some electric parts cleaner, I also pulled apart the connection for bank 1, sensor 2 and blasted that with the electric parts cleaner. The connectors weren't too dirty, but if it saves me money, I figured it was worth a shot.

I found this on TRS, and I would like to check out the voltage coming off the connector: Diagnosis Using The Oxygen (O2) Sensor As Ken and I talked about, it is indeed a 4 wire O2 sensor which is listed here in my wiring diagram as HO2S #12 (see image below). There is a black and a white wire, as well as a red and a gray wire; before I risk shorting out the circuit or burning myself on my exhaust, can anybody tell me which pair should be the one to prove whether or not the sensor is bad?

 

I tightened my gas cap a few days ago and threw in some fuel injector cleaner. Last night, I soaked the electrical contacts for my O2 sensors in electric parts cleaner, and then I cleared my codes.

I've driven the truck for over an hour and so far they haven't come back. This seems like it was all too easy, but I'll be glad if I don't need to buy a new O2 sensor or gas cap.

 

Apparently it takes the computer about 2 hours to set off a code. The P0455 is back, the P054 is gone, and now there's a P0430. Anybody have any knowledge on the P0430?

 

http://home.comcast.net/~miracerros/...wertrain_1.htm

 

looks like your catalytic converter is ready to fail
( i could be wrong though )

 

Ken, that's great info to have, thanks for posting that up.

I'm going to change out the #2 O2 sensor and hope that it is the cause...as one thing listed on there is a damaged O2 sensor. I found that as well searching around on the internet last night.

If that doesn't change it, I'm going to look into a misfire issue, and if that's not a problem, then I'll deal with the cat. I'm trying to go through the most possible issue to the cheapest possible issue, then to the expensive issues.

 

I just realized that the new code is for BANK 2. I think it has to do with the sensor whose wiring I cleaned up the other day on the driver side. Being that it wasn't throwing this code, I want to believe that it has something to do with that O2 sensor and not the cat, but I'm at a loss right now. I am going to try to find a way to see if there's any voltage changes over the O2 sensor. If I can't figure out what I'm doing or what's wrong the next thing to do is take it to a shop. I hate spending money on parts when my truck is running fine.

 

Just remember that cats don't fail without a reason. O2's will , but not always.
They (cats) have to be contaminated with something , gas , oil, or antifreeze.
Notice any engine fluids that require replenishing a lot lately ?

On another note , could you find some gas that doesn't have ethanol added to it ?

 

Good to know, hopefully the sensor that was all oiled up will be the problem. That sensor comes after the bank 2 cat... maybe that's the reason why I'm getting this code.

I haven't had the need to replenish anything recently, and no, there's no place that I know of to get gas without ethanol.

 

I have replaced the Y pipe, and the P0430 is gone, now I've got to tackle the P0455.

Does anybody know if I can check out the EVAP canister and it's components without taking the bed off of my truck? I tried checking the fuel filler line, but it's too hard to see with the stepside.

Also, does anybody know the part number for the fuel filler line and the grommet that connects it to the gas tank? Changing out the gas cap didn't help, so I feel that it is probably the issue that I am dealing with.

This what I'm dealing with, it is from the link that Ken posted:


P0455 - EVAP Control : System Leak Detected (No Purge Flow or Large Leak)

*After-market EVAP hardware (such as fuel filler cap) non-conforming to required specifications
* Disconnected or racked fuel EVAP canister tube, EVAP canister purge outlet tube or EVAP return tube
* EVAP canister purge valve stuck closed
* Damaged EVAP canister :
* Damaged or missing fuel filler cap :
* Insufficient fuel filler cap installation :
* Loose fuel vapor hose/tube connections to EVAP system components
* Blockages or restrictions in fuel vapor hoses/tubes (items also isted under disconnections or cracks)
* Fuel vapor control valve tube assembly or fuel vapor vent valve assembly blocked
* Canister vent (CV) solenoid stuck open
* Mechanically inoperative fuel tank pressure (FTP) sensor

 

bump

 

Don't make me drive all the way to Joisey to fix this for you.

Find the vac line going to the gas tank , mm K ?
Pull it off from where it connects under the hood , should be at a tee or at the sensor.
Start the truck and hold your finger over the connector you pulled the line from.
Got vacuum ?
If only a little or none check the canister and vac lines going to the intake manifold.
If good vacuum,check the hose and gas tank area.

 

Does the filler neck look fine, such as surface rust or junk on the rim?

 

Ken, drive out to Jersey for me and fix this damn thing! Ha.

Thanks for the info, I'll check out the vacuum line this weekend.

Mark, I didn't get a very good look at the filler neck. I will take a look to see if it is rusted over the weekend.

 

Since you have a body lift and didn't get a resolution by reseating the cap, you'll want to pay particular attention to the filler neck hoses and the lift extension, if present. Leakage there could easily give you a P0455.

 

Thanks Bob, I forgot about it, but that was my main reason I was assuming it was due to the filler neck after I ruled out the gas cap.

If it were my filler neck that was my problem - not the vacuum line, would that be as simple as replacing the 1" rubber hose, or is there something else that might be effected?

 

I was thinking of any hose connections to the metal filler neck which may have loosened since the BL was installed. I am not sure if your 2004 truck has a separate external vent hose like my 2003 or not. If so, then you'd want to look at connections at both the large filler hose and the smaller filler vent hose.

Of course, the leak could be any place in the sealed evap system. The filler neck occurred to me only because the body lift may have disturbed the factory assembly. If the location isn't easily found, you may have to go to a Ford dealer or independent shop that has a smoke machine and have them pinpoint it.