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New poster and starting with major frustration (not good way to enter this Forum world).
2007 F150 4X4 King Ranch with 5.4l. I will list out what has been done to get to where I am today....engine has 190,000km on it and has rough running during idle and will not carry load under regular driving conditions. The engine was running great until recently it started it's misfiring and rough running while I was on a 7 hour road trip which I began my troubleshooting while on the road. Pulled COP wires off 1 at a time and found no change to idle on 5,6,7,and 8. Suspect plugs to be culprits as I do not know history of their life service. Tried the parking lot removal of #5 and broke it so decked truck and brought it home to my garage where my tools were and extractor tool was used.
New plugs installed (Motorcraft). All but 2 broke coming out so used the extractor tool successfully (thank god for it).
Started and still had same issue. Rough idle and sounded terrible.
No scanner in hand at this point so was trying old school ears and eyes troubleshooting method........yes, this method is deemed unreliable due to age and technology (but all I had at the time)! Fixed this problem with a Mac tool device later on in my story.
Figured Fuel pressure is not a concern (as measured with scan tool later on when I got it) as made a conclusion that if this is limited to a single bank of 4 cylinders that fuel would effect the entire engine and not choose the bank under the entry point on the rail.
Immediately sounded like a plugged cat (similar experiences on a different vehicle) so I immediately removed both pipes from exhaust manifolds.
At this point I confirmed bank 2 was guilty culprit as mis-fire sounds coming directly out of bank 2 only. Bank 1 sounded like a symphony (the purr of 1/2 of a V8!). No change to results.
Removed new plugs both sides and noted bank 1 were clean and bank 2 were black/dark grey (rich in my opinion).
Swapped side to side (bank 1 for 2) plugs and restarted and problem did not follow. Still bank 2 misfiring.
Pulled wires off #5 COP.....no change to engine sound. Same results for all bank 2 cylinders (once I had 5,6,and 7 unplugged the engine finally gave me some feedback that it was having hard time idling on 4.5 cylinders).
Swapped all COPs from bank 2 to bank 1. Same result....bank 2 still misfiring
At this point I secured the MAc Tools scanner and went deeper into the diagnostics.
I will point out that there were no mis-fire codes being logged! No codes for engine or emissions whatsoever! I pulled codes with cheap code reader as well as the fancy Mac tools device.
Spent weeks scouring online forums for directions.....TONS of great info but none could help me with bank 2 (all 4 cylinders) showing erratic firing but not logging codes. (see attached graph of Power Balance).
Was lead to ensure no vacuum leaks....I drained 4 cans of brake clean spraying down every vacuum line and fitting and manifold gasket inside and out, as well as the manifold itself on the engine (including the vacuum manifold behind the battery and the ever impossible main line off the back drivers corner of the intake manifold!). No changes to STFTs bank 1 or 2. They remain steady and show no signs of unmetered fuel entry. Made conclusion vacuum system is tight.
as you can see on graph I have 5 & 6 showing the worst in the balance graph....so removed injectors and swapped to 1 and 2 position. Same result....all 4 on bank 2 dropping out erratically.
Unplugging cam position sensors on either bank did nothing. No codes nor run ability results.
Cleaned both cam position sensors, nothing on them.
Performed compression test with scan tool (cranking engine for 10 seconds KOEO) and all cylinders show same results except 7 and 8 are down a tiny little bit (compared to the other 6). By the looks of the graph and firing order, if 5 and 6 were suspect to be low compression, I can assume the tool would pick up the speed of those 2 cylinders cranking especially being one after the other in the order. Conclusion made that compression is fine. 7 and 8 known to be guilty 1st ones to wear out (or so I've read in the countless late nights of reading forums).
Connected the exhaust back to the exhaust manifolds to put cats back into play and still same result.
swapped ignition capacitors from bank 1 to bank 2 and still same result.
all COP wiring harnesses have 12.0V engine off key on.
One thing to note is that key on engine running when I pull plugs off any of bank 2 injectors, the power balance does not jump around like the picture shows, it actually drops off and stays low and steady. Plug back in and immediately the cylinder starts it's erratic pattern of firing as shown in the graph pic attached.
Under load (torque stall in reverse) the bank 2 cylinders drop out even more noticeably and the exhaust sound from the bare exhaust manifold clarify that indeed bank 2 is dead and/or misfiring alone. Bank 1 is sounding as it should (as well as showing well on power balance screen on scanner)
Questions for the group......
Am I focussing on the Power balance screen too much?
Am I missing something glaringly obvious?
Is it possible the PCM lost ability to fire bank 2 cylinders reliably and strong?
I can answer any and all questions and will not have hurt feelings. Am always willing to learn from anyone!
Update.......limped truck to the Stealership......provided them the run down on what I have done to date. Gave strict instructions to Service Manager that I had a very peculiar problem that I did not want a parts changer to look at and that it needed his oldest most experienced tech to tackle. Suggestion made to reflash the PCM and check it out from that point as I have completed all the things they would have done. More to come.......
The previous evening I topped off my truck with premium fuel at a corner store off the highway prior to driving home, I traveled abiut 36 miles to my exit and when I got off the interstate and pulled up to stop at a red light my truck began running unpleasant. I checked for codes with my scanner and got a P0305 and P2198. My fittings are 5 months old and I reassessed from chamber 5 and it was fine. I supplanted the loop pack, cleared the codes and clean the MAF. Then my truck struggles with beginning which tossed more codes. Presently I have codes P2198, P0308, P0305 and P0300. So everything is by all accounts connected with the one side, any ideas?
Update 2.......old tech at dealership reflashed PCM. No change. More troubleshooting and pointed at cam timing perhaps jumped a tooth. Took truck home for disassembly to manually check cam timing. More to come........
Stripped front end and removed valve covers. Found links on chain (which is not a great indicator but felt it necessary to guage any previous work before I got the truck). As you can see by pics...... Bank 1 cam is "close" to 12 o'clock and bank 2 is about 11 o'clock...... And crank is tdc on vibration damper. 1 revolution of crank switches sides with markings..... Bank 1 stays a wee past 12 o'clock but with the early Gen phazer markings (the dash) and bank 2 stays about 11 o'clock but with the indicator arrow....... Also to note the phazers looks to be holding true and have not let go as the middle finger of the tone ring is directly over the indicators on both gears...... So indeed it looks like a timing chain jumped a tooth or 2 on bank 2. Cover is coming off to assess guides and chains and other components as glc indicated. And yes previous workmanship indicates sloppy job as chains never line up with marks on cams (dark links marked yellow) which is only indicator of quality of workmanship prior to me digging in.
Bank 1 arrow just a lrch past 12 Bank 2 at about 11 Crank at tdc
@glc I have parts on order. But while I wait, I removed chains with cams locked with vice grips and marked so as to ensure they don't move. Just trying to make sense inside my own mind.....since I am able to install the chains with marks lining up to the crank gear and the phazers, is it possible the chains are stretched enough that would allow the timing to be "out" enough to cause the mis-fires on bank 2? I know I will be able to compared new to old once I get parts in hand but I needed to vhet this question to see if it is "plausible". The gears are definitely not thrashed as I would expect to see if chains were excessively worn, but then again I have no idea what was done prior to my disassembly. Maybe someone put new gear and phazers in and left chains?? Anyways......just looking for pontification on stretched chains plausible for bank 2 misfires.....
Ok.... Update 3.0......i have installed new phazers, guides, tensioners, chains and crank gear as well as the high pressure high volume oil pump and new solenoids and valves for camshafts. Primed pump and assembled engine and started up. I did find both phazers had broken pins that tension the springs so they only had the hooped end secured by the pins. I figured I had the smoking gun. Upon start up the bank 2 erratic misfires returned..... Or did not go away. The engine sounds like a brand new one and has never sounded so smooth mechanically. Top end is like a Swiss watch. The misfires on drivers side is going to be the death of me.
Just my hunch now but am leaning towards the PCM having a faulty driver's for the bank 2.
The tech at dealership checked the compression manually when I tried the reflash and they said there was no concerns noted..... But I did not ask what the value was. Made the assumption that if compression was of concern they would have faulted it as a contributing factor. The only thing I have not done is replace the PCM. It is the only thing I can determine that would drive a single bank or 4 cylinders to misfire at the same time consistently, now that timing is out of the way as a concern.
OK, so here is latest update on my saga.......I drove it to the dealership and gave them another complete run down on what I have done to it...... I have performed a complete timing set replacement. New everything. Phasers, tensioners, chains, guides, gear and high volume/high pressure pump. Followed directions as instructed on video posted above. Assembled and started and same exact thing. Bank 2 (drivers) has erratic firing as per the original pic posted on Power Balance screen. At this point I am at mercy of dealership help as they are to be supposed professionals. They looked at it again and questioned the timing.....again. I assured them I had timed it correctly but they stuck to their assessment of bad timing job on reassembly. They also mentioned that cam bearing caps were scored up pretty bad and that loss of oil flow out of the caps could also contribute to phaser operation. I am not sold on this diagnosis at this point. Especially with brand new high volume/pressure Melling pump installed. But being at their mercy, I agreed to disassemble and re-time it with very vivid and detail oriented pictures and video to prove that timing was not a factor. Drove it home and disassembled front cover and removed plugs and then put kid in charge of turning engine over by hand to line up timing marks (as I had set them upon new parts installation just prior). Sure enough my timing marks lined up perfectly. I then took pictures of my timing job, then removed each cam-shaft and took pictures of the bearing journals myself for my own records. I then installed the cams back and started timing from fresh, following the service manual provided by the dealership. I took pictures along the way to ensure I could prove to them the timing was exactly as they have recorded in the manual. I will not bother with attaching pictures at this time as I figure if you see once, it is basically the same. It is timed perfectly. I also removed the solenoids from the head and cranked over the engine with starter (manual engagement with battery) and verified oil flow into the solenoid cavities as well as good oil flow out the cam journal caps. This satisfied my question of whether there was enough flow to properly lubricate the top end as well as operate the phasers. This was all at cranking speed. Made assumption that at idle of 600rpm there would be plenty of oil to top end. Anyways......as a last ditch effort to try one last thing, I swapped VVT solenoids and cam sensors when installing them. Put remainder of engine together and started it up and the exact same problem existed. The power balance screen showing bank 2 very erratic and bank 1 very solid and consistent. Basically nothing changed.
I am now "invested" and cannot let this thing beat me. I am not above begging for help. I have not returned to dealership as of yet but will be taking it there in the next few days for another assessment now that timing is out of their way. My fear is that they will point to oil flow and hang their hat on that. My question to the group here is this.....with drivers bank getting flow of oil before passenger bank, would it not be safe to assume that if any bank was going to act erratic it would be the end of the oil flow line (aka passenger bank 1)? Am I correct that oil flow ends at passenger bank top end?
PCM question.....If I was to remove a PCM from a very similar truck....2007 F150 5.4l 4X4 regular gas (not Flex fuel) would the dealership not be able to pull PATS info from mine and flash into (new to me) different PCM and then I can eliminate that from the troubleshooting procedure? I am still leaning towards a bad set of drivers inside PCM for bank 2. I know PCMs are rarely to blame but I am at the end of the rope here. The only 2 things I have not replaced are the PCM or the wiring harness.
@glc what do you think? Have I missed something or what are your thoughts on the PCM question? Not sure if you are able to verify which part numbers of PCMs will work for my replacement idea. I have 2 from auto-wreckers currently. 1 from a 2007 and 1 from a 2006. Both are non-flex fuel but 5.4l engines..
