Since my previous thread on re-doing my engine's timing was getting a bit off-topic by delving into this subject, I figured I'd start a new relevant thread to the specific issue I'm dealing with now. (I swear, if it isn't something, it's something else with this truck...)

Long story short: Re-did timing chain, tensioners, guides, etc. That all went well... time consuming, but well. Took the truck for a test drive, felt a shudder around 45-55 mph while in Overdrive. Ordered new Motorcraft SP515 spark plugs and installed them without a single breakage. Took the truck for test drive #2, 45-55 mph shudder was still present. Drove back home, and felt a major shudder while idling, something that had not previously occurred.

I pulled each COP and tested them with an Ohm-meter. They all seemed to be good, so I ran a cylinder balance test (disconnect/reconnect fuel injectors one at a time to feel for a drop in RPM's. No drop=culprit cylinder) and things appeared to be the fault with cylinder #4 (farthest back cylinder on the passenger side) The pigtail connector to the COP has an apparently bad seal, as the rubber is split and partially jammed up inside the plug. For posterity, I swapped coil packs with cylinder #1 and swapped injectors with cylinder #2 and re-performed the balance test. Cylinder #4 still seemed to be the source of troubles, so I ordered a care package of parts from Amazon including new pigtail connectors for both the COP's and the injector on cylinder #4 (just to be on the safe side)

I also decided that investing in a scan tool would probably be a good idea, so I ordered an Innova 3040d tester. Hooked it up to the truck tonight, and it gave me the following codes:

P0204 - Cylinder 4 Injector Circuit Malfunction (though this could have been a result of our repeated disconnects during the balance test)
P0351 - Ignition Coil A Primary/Secondary Circuit Malfunction
P0354 - Ignition Coil D Primary/Secondary Circuit Malfunction
P0356 - Ignition Coil F Primary/Secondary Circuit Malfunction

The scanner didn't detect any misfires reported by the truck, which is surprising given that when I shift from Park into Drive with my foot on the break, the whole truck starts shaking pretty roughly. Not sure as to whether any of the codes were holdovers from our swapping COP's and injectors about, I erased and reset the codes. The reader now shows no DTC codes for Freeze Frames, but the status light says that there are 'pending' DTCs and that there may be a possible problem.

So tomorrow, because it's ridiculous-o'clock as of right now and I should probably get SOME sleep, I'm going to start by replacing the cylinder #4 pigtail, and potentially one or more corresponding COP's.

Is there anything I may have overlooked with these codes? I'm planning on taking my family camping this weekend, but without the truck to haul the camper, we're kinda SOL. The Explorer is a V6 and is trusty as hell, but it doesn't quite have the horsepower/torque to haul the camper reliably up over mountain passes. -Plus it's not wired for trailer lights, and I'm really not in the mood for another car project after the past 2 weeks.

 

But the problem is more like cleaning all the cop connectors .
Breaking new plugs do to forcing it in thru carbon build up around spark plug tip . Guys blame this on getting a new one bad out of the box . Use a rubber sparkplug socket, go by feel in starting them ,no power tools . Use your fingers, if you cleaned it right they should go easy all the way .
Use a rag on a crimped wire with carb cleaner to clean those cyl areas out . It will dissolve that carbon and no cleaner in the fuel or seafoam can reach it .
Failure to change out old boots is common . The boots hold back 30000 volts between the springs and the heads . Unless you possess a high pot tester capable of testing boot at 30kv then the only sensible thing to do is replace them . I can't believe the aggravation guys go thru because they fail to replace them all . They are cheap!
Torque spark plugs in 25 to 28 foot pounds with a torque wrench not by feel . Use a dab of dielectric grease on each end of the boot but not on electrical connectors it is an insulator not a conductive gel . It stops moisture and stops heat from seizing boot to plug .
I change my plugs around 60k and I use a very small amount of antiseize on threads ,nickle stuff only . Keep your hands clean don't contaminate high voltage parts .
Cop bolts seem to get corroded and snap off, best to put a little anti seize on them . Especially if you are in salt country .
Don't use off brand stuff, stick with oem parts . Ignition system on this engine is very fussy . 60k is a long time, do it right . Cops rarely go bad clean them up ,I didn't have any luck with after market.
Misfires have to last a long time to set codes, it is hell on the cats to force it to. Cats cost a lot of money and so does having your plugs done . They charge $300 - 800 plus parts and frequently don't do it right .

 

I replaced all my injectors at 100k and will again at 200k . They work hard and this generation had a bad rep . They are not cheap but they can cause damage . I guess I could build a test and clean setup but anything that mechanical plus electric only lasts so long and I'm not going to buy rebuilt ones either .

 

FUN with Misfires?

As I commented in the OP's original thread: "The low (1150-1500) RPM misfire has driven many 5.4L owners to drink."


I agree with everything @redfishtd has advised. He knows what he's talking about from experience with his truck and work experience with high voltage stuff.


I do also note that your ignition codes are all 'circuit' related instead of indicating sparkover to ground instead of plug tip - which will produce a code P030x instead.


The design of PCM ignition circuitry (+ to COP primary, and PCM grounds the switched leg of primary coil - then releases it to induce spark in secondary windings) allows the PCM to know a lot about what is going on in that circuit. It can detect open or ground in the COP primary (no '+' present in switched leg when it is not grounding it). It can see the reverse EMF ('kick back' voltage) when it grounds the switched side then releases it. If the COP secondary coil is 'open' or has a bunch of windings shorted together - this 'kick' is non-existent or not as robust and the level of reverse EMF will _NOT_ appear to have produced a spark in the secondary - or the plug.


Under THESE conditions, the PCM does not increment misfire counters. In fact I do not believe the PCM even checks for misfire indication (dip in crankshaft rotational velocity) if this phase of ignition is not good. It truly is NOT technically a misfire (30x), it is a different problem (35x) and is reported that way.


I would drill down on clean connectors to all COPs and clean all electrical connections to the PCM - etc (with battery disconnected of course).

 

If I say how I REALLY feel about it, then the truck wins.

I did follow your recommendations when changing out my spark plugs, frankly every thing you said made so much sense, I'd have been crazy not to do it. Definitely cleaned a fair bit of crud out of the ports, though I took a slightly modified version of your tool. I didn't have any wire handy at the time, so I took a long rag and wrapped it around the tip of my second-smallest nylon brush, then blasted that part with carb cleaner and ran it through the spark plug port, switched to a clean part of the rag and repeated as necessary until I was satisfied that the rag was coming back clean. Brilliant thinking on your part, as much sense as it made doing it, I don't know that I'd have ever thought of that on my own as a problem area.

UPDATE:

Having cleared all the codes last night, I did my best efforts to do the Ford drive cycle from memory this morning. My truck did NOT appreciate it, especially in overdrive between 45-55, it was shuddering/shaking so bad it nearly gave me whiplash. (slight exaggeration)

I got back, turned the truck off and re-linked my scanner. Upon boot up, it gave me a new code: P0304 - Misfire in Cylinder 4, confirming what I suspected from the engine balance test.

None of the other codes came back. I talked with my buddy, who was doing the plugging/unplugging during the balance test. He admitted that he had pulled the ignition wires on those cylinders the second time we ran the balance test after swapping COPs and injectors. So my guess is that the multiple times we pulled the pigtail to the Cylinder 4 injector probably triggered the P0204 code, and his pulling the ignition harnesses for Cylinders 1 & 4 after the COP swap (before I realized what he was pulling and had him switch back to pulling injector pigtails) caused the P0351 & P0354 codes. As for P0356... he thought he felt a change in the engine's RPMs when he pulled the injector harness, so when we tested that cylinder a second time, he switched over to pulling the harness from the COP.

Again, all the above is pure speculation. I don't profess any major technical knowledge when it comes to this area of vehicle repair, so I could be totally wrong in my assessment. I've got some work to do for a bit yet this morning, but I'm definitely going to replace the ignition harness on cylinder 4 to start with because of the failed seal. I'm also going to pull that spark plug and do a second check on that port just to be sure. But in the meantime, if anyone has any additional input, I'm all ears.

 

I had an advantage (if you can call it that) on mine. With 120K on my first set of plugs (Stupid & won't happen again), the second set of plugs I noted they literally 'screeched' on removal - exactly like rusty lug nuts will do. THAT's when it occurred to me that forcing new plugs into that environment would have to have a ninety-nine percent chance of screwing up the snout on a new SP515. They weren't bad out of the box - but after I used a ratchet to get them screwed in. My third set of new plugs went in by finger all the way to the seat. All that made me a believer.


Sounds like you are doing all the right things. As @redfishtd states, the Triton is very 'picky' about ignition. The Triton runs at the extreme edge of everything (lean - low RPM torque - cam retard - high voltage spark) for maximum fuel economy. _Anything_ not just perfect seems to result in misfires.


I can't 'rationalize' how injectors could be more likely to deliver inconsistently under light load (45-55 mph in OD). Though I have frequently heard they are problematic on '05 models. I have changed mine and it runs unbelievably smooth - though they were replaced as part of my timing job - not related to my curing misfires 60-70k miles before the timing job. I am a believer they do not last eternally.


Do you have the ability to get some live data to verify some other things that 'could' play into the issue. ie. Fuel Rail Pressure, FPDM % duty cycle, STFTs and LTFTs, and maybe O2 sensor readings. (Have you changed O2s? - another _RADICAL_ opinion from F150Torqued's library of radical ideas is that O2 sensors are designed to provide the PCM electrical feedback that is calibrated to 14.7 to 1 fuel/air ratio. BUT THEY BECOME LAZY AND OUT OF CALIBRATION. That means that when the PCM 'Thinks' it has fuel/air ratio just right --------- IT AIN'T. I am a believer in replacing them as a matter of PM @ 100k whether needed or not.

 

Just an FYI, but about 50 mph in OD is where the PCM maximizes the EGR flow - and that leaner mixture needs lotsa voltage to get it to ignite.

And since cyl #4 keeps popping up, even after changing stuff all around, maybe it's the cylinder. Might be worth a compression check to be sure it's not a mechanical issue confusing the PCM.

 

^^^^ Good points ^^^^^. I've learned more than a little from @pdqford. In fact - I learned 035x events do not count as misfires trying to 'show him a thing-or-two' --- that blew up in my face! I was unplugging COPs trying to prove Fuel Trims would go negative _due to a resulting over-rich condition_, and learned the PCM is quicker and smarter than I am. It refuses to energize the injector when COP experiences circuit malfunction (P035x).


EGR effect (accomplished by cam retard on OP's Triton) creates max lean condition / and lowest compression due to retard at about 50 mph in OD (1100 - 1200 rpm). EVERYTHING's got to be just about perfect to not misfire.

 

What a waste of time and money. I have tested the coil pack, the coil harness, the injector harness, and even though all were good, well gee, something is still wrong because the truck shudders and shakes like a dog trying to pass a pinecone. So what the hell, I already bought the parts, might as well try replacing them. I've swapped out the COP, removed and re-checked the brand-new spark plug, replaced both harness connectors on the fuel injector and the coil pack. Started it up and it began misfiring just as bad as before. Still throwing the P0304 code, plus when I put it in gear, it almost bogs down and dies; just backing out of the garage my RPM's dipped down to almost 400 and I honestly thought it died for a hot second. I've tested the compression, I was able to roughly measure 180 PSI. -I say roughly because I didn't have an adapter that would thread onto the cylinder, so I was trying to hold it by hand and it was generating enough pressure that I couldn't keep it in place very well.

What have I accomplished? Nothing. I need the truck to pull the camper, so our weekend camping trip is ruined, and my family is pretty upset about it. I have wasted so much time and money on this stupid thing the past 3 weeks, and all I've managed to do is **** off my wife and render my truck utterly undriveable. I'm about to swear off Ford forever after this complete fiasco. -Sorry if I sound dramatic, I'm just really worked up right now and just need to vent a little. I almost reached the point where tools started taking flight inside the garage.

I'm at my wit's end. Short of replacing the fuel injector, there is nothing else I can think of that would be a fix that doesn't involve tearing open the engine and dealing with a lot more crap that's beyond my pay grade. And frankly, replacing the injector doesn't make sense, because cylinder 4 was already misfiring when I first did the balance test, so I swapped the injector with cylinder 2, but cylinder 4 continued to misfire.

I honestly don't know what else I can do... at this point, I'm just going to throw myself at the mercy of the Internet and hope that someone smarter than me can think of a solution that I've overlooked. I could really use some help.

 

Oh, one other thing... when I shut the truck off for the last time, there was a sustained hissing sound from the passenger side of the engine. I have no idea if this is a normal thing or not, but I figured it's worth mentioning for posterity at least.

 

Definitely scratching my head . This hissing doesn't sound normal to me . But I don't know what the tie in would be . Your engine vent pcv system returns to the throttle body at the passenger valve cover is the only thing I can come up with.
Is the engine making any noise on the passenger side . I 'm thinking about lash adjusters or rollers on no 4 or a stuck valve closed . I 'm also thinking about tone ring on crank shaft sometimes broken guide pieces damage that toothed ring . One guy was chasing misfires and it ended up being that . I don't know that you had broken guides or not .Mine had severe broken guides plugging oil pump screen but tone ring okay . I replaced all lashes and rollers .
My lash adjusters were so bad that it threw number 8 intake roller to the side it sounded terrible . The roller pivot was bad and it was gouged but didn't damage cam . I didn't have a scan tool and had no choice but to tear it down so I can't say how it would have shown up .
In case you don't know the cops have standing 12v dc on one side and are jumped to other cops ,the pcm has the other side wired to it and it pulses the grd to that side. One test to do would connect a lamp to number 4 cop and then the injector to see if they are pulsing . A grounded wire will short that out causing a full light no pulse . or an open will show up (broken wire) no light . PCM output can be damaged to any cyl on an overload or short .
Just in case I missed your sequence of cleaning etc , That plug on number 4 can we see another one in its place just in case it's bad somehow ,it happens sometimes .
I know number 4 is the worst one to have trouble with. No 4 looks like dark green with violet stripe .
I reseated my pcm plugs after cleaning pins with contact cleaner .

 

oops double post

 

All good ideas @redfishtd. I may be misinterpreting part of it but wanted to add, or caution. This thing does look a little like it could be an output circuit to COP #4. But - testing the PCM 'output' circuit is a little tricky. An 'incandescent' bulb will NOT work successfully for three reasons (1. it is not fast enough to respond to the short duration grounding by the PCM. 2. An incandescent bulb's cold filament has ZERO ohms (a dead short) before it becomes white hot (reaches candescence) and can BLOW out the PCM output driver transistor. 3. The reverse EMF of the collapsing coil primary field can BLOW the filament out of an incandescent bulb.


Unfortunately - in my view a noid light (led) has similar problems in that they do not require enough current in the circuit that their lumination does not conclusively prove the PCM output circuit is good.


It is my opinion that the only successful way to check the PCM's COP output circuit is to verify electrical integrity of the harness - then - connect a spare COP to it with a spark plug attached, ground the plug and run the engine (a short time) to see if it is capable of producing a spark. OR use a high voltage spark testor.

 

I didn't say noid light but I should have , nor do I have one , I needed one at work just before I retired but didn't get one . I used my scope at times . And I haven't actually tried this test . I don't have a spark tester for this engine either . I know you have one . I do not have the compression adapter for this engine either .
I am not experienced in the compression tester anyway , I know to compare one cyl to another . I had an old kit but it got loaned out and it is gone . If I jump in to help someone locally I would get one . I need to get experience on it anyway . I don't know how to see if valves are opening for sure and 3v is even more complicated .
Last fella I helped the other day couldn't get his injectors in didn't really want to believe motor oil on o-rings did the trick on his new plastic intake ..
But I did blow up my wife's toyota coil testing it by jumping test to block for spark, man it blew up fast . Cost me some bucks .
I guess the best test would be the spark tester . This one is a lisle ?

 

Now that I'm NOT considering taking an acetylene torch to my truck to teach it who's boss (okay, I'm still considering it a little bit), here's a bit more of an in-depth follow up.

Just before I did the timing job over Memorial Day weekend, I had dual exhaust installed and I ran some Lucas injector cleaner through the tank. The truck was running STRONG, engine power was there and it ran smoothly.

Did the timing job, replaced the tensioners, chains, cam sprocket. Didn't do phasers because the Ford parts were pricing themselves out of my budget at the time, however prior to the install, I had a mechanic give it a look over and he said he didn't detect anything that sounded like the phasers were going bad. He even hooked up his high-end tuner and ran over everything in the engine just to be sure. He even said that if the phasers were still good, he'd recommend keeping them instead of replacing with any aftermarket brands.

After the install, I took it for a test drive. Ran beautifully at first, but when I hit 45-44 mph, the truck started shuddering. When it sat at idle or ran in any lower speeds/gears, it ran smoothly. The shuddering only occurred when driving at the above speed/gear combination.

Bought a full set of Motorcraft SP-515 spark plugs. Removed all my coil packs the night before and blasted every plug with PB Blaster. I also got some Blaster on other various areas around the spark plug ports as well... it's pretty tight in there to fit a can of something and spray accurately, even with a straw. At any rate, the next day I removed all the plugs without a single break, and installed the new ones. I put a dab of dielectric grease on each boot before inserting them onto the plugs, then a little dab on the injector harness for good measure. (I know it's not conductive, but the tight fitment of the prongs would displace enough grease for a contact point, leaving the rest to insulate it. -At least, that's how I understand it) I started the truck, everything ran normal. Took it out on the road, hit 45 mph in overdrive, and the shuddering returned. Got back home and shifted into park, suddenly the whole truck was shaking.

In order to figure out the source of the trouble, I did a cylinder balance test, since I didn't have a code scanner at that time. Unplugging each fuel injector one at a time, we felt/listened for a change in RPM's. When we got to cylinder 4, there was no change, indicating that was the problem area. Swapped out coil packs with cylinder 1, and swapped the fuel injector with cylinder 2. Started the truck, and the misfire continued. We again ran a balance test, and again cylinder 4 was the only one that didn't affect the truck's RPMs at idle when we disconnected the injector harness.

So I got on Amazon, ordered a full set of ignition harnesses, a new coil pack, a new fuel injector harness, an HEI spark tester, a code scanner and two new VCT solenoids & seals (saw too many people recommending installing the new OEM design to ignore it, plus compared to everything else on this truck, installing them was a breeze) I connected the code scanner, and it initially gave me 4 codes as I mentioned in my first post: P0204, P0351, P0354, P0356.

Yesterday, I cleared the codes and took it for a drive. Came back, plugged in the scanner and got just one code: P0304. Ran it a bit longer to test a few things and for the first time ever, the MIL light came on. Re-connected the tester, and it came back with the same P0304 code. Last night, I tested everything. First I tested the existing coil pack and ignition harness with the HEI tester. It fired a nice blue spark and appeared to be firing in sequence with the rest of the engine. Used a Blue Point multimeter to Ohm out the injector's terminal, it tested out within the normal operating range (I don't remember the numbers off my head, but I did find what it should be running at and it complied) Connected a 12v power supply to the tabs of the injector, it began ticking/firing like it should. I backed the spark plug out to check for any oil or coolant residue on the plug, totally clean. I inspected for any carbon tracks, but the plug was clean. My buddy Ohm-tested the plug, and it passed that as well. While the plug was out, we ran a compression test, and as stated above we got a reading of about 180 PSI, although it wasn't a continuous reading because the we didn't have an appropriate adapter to thread onto the block, so it was held on by hand. There was enough pressure that keeping it in place was impossible.

For lack of any better ideas, we cut the original ignition harness (it had a bad seal anyway) and installed one of the new ones. The engine kept misfiring just as bad as before. Installed the new coil pack to see if that made any difference, no change. Cut the injector harness and put the new one on, even though there was no indication of failure from the original, we were nearly out of potential fixes at that point. Every time, the truck continued to misfire just as bad. So, I kicked my 3 step ladder, aimed a few more curses at the truck punctuated by a couple kicks to the tire (it was 1am, I was tired and hadn't eaten anything since noon, so I was already extra cranky) went in and, well, that's how my previous post came into existence.

I've uploaded a video of the engine running. It's from a cold start (I was in a rush this morning) but the engine sounds the same warmed up as it does cold. There's no noise associated with the misfire, the whole truck just shakes and when I put it into gear, the RPM's drop down to 500 or lower and it sputters and nearly dies.

You can take a look/listen here: