Random Misfire, Loud Engine Knock

[MattChadwick]

My 5.4 that I've only had for about 200 miles started randomly misfiring in cylinders 2,3, and 4. It has a very loud engine knock, sounds almost like a diesel at this point. I'll be driving down the road and the engine will lose practically all power, but eventually will gain it back. It started giving me a blinking engine light, so I got the codes read and it gave me plenty to ponder on. For the record, I changed the Camshaft Position Sensor and VCT solenoid and neither has worked so far. Here's the codes I got:
P0172 Bank 1 too rich
P0174 Bank 2 too lean
P0300 Random Misfire
P0302 Misfire Cyl 2
P0303 Misfire Cyl 3
P0304 Misfire Cyl 4
P0340 Cam Sensor Bank A
P0344 Cam sensor intermittent
P2916 O2 sensor stuck rich B1S1
P0138 O2 circuit high voltage B1S2

Obviously, I have a feeling that it's the O2 sensors, but why would both sensors go bad at the same time? Any insight helps. Thanks.

 

[Habbibie]

By you saying you changed VCT's it leads me to think you are driving a 05-06 5.4L 3v expedition, anyways All these codes all at once tells me Your timing is off, possibly chain jumped a tooth or cam phasers are shot. Get the timing chains & phasers inspected before you go spending a bunch of money chasing after each code which i guarantee will not get fixed until timing components are fixed.

Also this is a good time to check your oil pressure,

And finally be prepared to spend a lot of money in repairs and possible towing if you're gonna keep driving it...

Been there, done that.

Best of luck bud.

 

[Bedrck47]

Obviously, I have a feeling that it's the O2 sensors, but why would both sensors go bad at the same time? Any insight helps. Thanks.

Anytime you have codes that indicate O2 problems along with other codes you need to fix the other codes first. Remember, O2 problems are caused by problems upstream of the O2 sensors

Agree on what Habbibie is telling you he has "Been there, done that"

 

[docraymund]

Yup with what you are describing, I think you have a pretty worn out engine. Cut your losses now and sell it.

 

[Bedrck47]

BTW

Welcome to the forum

Other than listing your location as USA which most members are from Its nice to know your state.

However in your case and from the description of your problems I would guess your in the
State Of Confusion

 

[stamp11127]

Hey since he is at the ripe old age of 17, smart enough to read the codes and list them, type a sentence without the modern abbreviations and ask for help...you have come to the right place.

Welcome to the forum.

It would be better for us to post more info such as year, mileage, 4x2 or 4x4 etc.

Rule of thumb here is to diagnose first then throw parts at it if nothing else works.

 

[Bedrck47]

There is no P2916 O2 sensor stuck rich B1S1 for the Expy

Did you mean P2196

P2196 - O2 Sensor Signal Biased/Stuck Rich - Bank 1, Sensor 1
Description: A heated oxygen sensor (HO2S) indicating rich at the end of a test is trying to correct for an over-lean condition. The test fails when the fuel control system no longer detects switching for a calibrated amount of time.
Possible Causes: See the possible causes for DTC P2195.


P2195 - O2 Sensor Signal Biased/Stuck Lean - Bank 1, Sensor 1
Description: A heated oxygen sensor (HO2S) indicating lean at the end of a test is trying to correct for an over-rich condition. The test fails when the fuel control system no longer detects switching for a calibrated amount of time.
Possible Causes: Electrical:

• Short to VPWR in the harness or HO2S
• Water in the harness connector
• Open/shorted HO2S circuit
• Corrosion or incorrect harness connections
• Damaged HO2S
• Damaged powertrain control module (PCM)

Fuel System:

• Excessive fuel pressure
• Leaking/contaminated fuel injectors
• Leaking fuel pressure regulator
• Low fuel pressure or running out of fuel
• Vapor recovery system

Induction System:

• Air leaks after the mass air flow (MAF) sensor
• Vacuum leaks
• PCV system
• Improperly seated engine oil dipstick

EGR System:

• Leaking gasket
• Stuck EGR valve
• Leaking diaphragm or EVR

Base Engine:

• Oil overfill
• Camshaft timing
• Cylinder compression
• Exhaust leaks before or near the HO2S(s)

 

[Bedrck47]

Matt I am normally one that doesn't like to make guesses but I will in your case.

I am guessing that since you purchased the expy and state you have put only 200 miles on it so far. That when you got it there was no Check engine light on. That is because all the codes were cleared before you looked at it and purchased it.

It appears that you purchased someone else's headache.

Before you go and throw parts at it trying to solve the problems Please take the time to troubleshoot the problems.

There are some very good members on this forum that are willing to help and give you good advice.

What you need to do is listen and also answer any and all questions that are asked of you. The better the information you give will aid in the replies you get. If you are unsure of something just ask.

Now back to your O2 sensor problems.
The wiring for those sensors are very close to the exhaust systems.
You need to check the wiring harness for any signs of overheating/burnt wires.

Read Stamp11127 post and provide the information he requested.

Consider getting yourself a copy of the Ford Service Manual on DVD. Don't waste your money on the aftermarket manuals, they are not year and model specific. The Ford manual is specific to your model and year and should cost you less.

http://www.expeditionforum.com/threads/factory-service-manuals.25089/

Let us know your skill level electrical and mechanical

 

[MattChadwick]

Wow, I was not expecting all the replies, so thank you guys for jumping on this so quick. As far as my skill level, I'm pretty mechanically inclined, while also pretty electronically declined. Before this, I had a 2003 Jeep with an inline 4 engine. Pretty bare bones. I bought this hoping it'd be something more reliable and realistic, which have both backfired on me. I don't have all the tools that I wish I do, such as ones that help with diagnosing the problems, and definitely don't have the money to put into this car- even for a diagnosis. I figured I'd start with the CMP sensor and VCT solenoid and after that work my way up. I do have the 2006 Ford Expedition with the 5.4 3V engine. I have to add some more details into my account but I was in a rush when I made it. Nevertheless, I also have a feeling it's the cam phasers, but was just really hoping it was not. Thought I'd get lucky with the VCT solenoid. So, I'll probably have it checked out by someone that can help me diagnose it with tools better than mine. I considered the possibility of the chain jumping a tooth, but wouldn't that eventually throw both banks out of balance? But who knows, the possibilities are endless with this one. I'll get this checked out. Thanks guys.

 

[Bedrck47]

Matt Keep this in mind Its a V8 therefore it has TWO timing chains and its possible that only one could jump a tooth.

Help is here if you need it and the two best things about help from members is it's mostly good help but its also free help.