Ford 5.4 One bad spark plug can spoil the whole bunch

[Winger Ed.]

Over the last couple years, and 2,000 miles I've been taking the '06 F250 with 59-61,000 miles on it through
what I call a vehicle's 'mid life crisis'. I normally do this at about 100,000 miles, but my driving is mostly in town.
So I figure it has about as many spins on the engine as over 100,000 if it had seen much free-way miles in overdrive.

So I changed plugs and coils. A little while later, it started running rough. A couple of the aftermarket coils had gone bad,
so I changed 'em back to OEM. It was better, but not right.

I try to keep this thing in perfect condition. If I want to go on a long trip-- its ready. Nothing needs fixing first.
And when everybody else breaks down--- they call me. If my car breaks down, I'm on my own.

Anyway- it set some lean codes. In my research through videos and old forums where everybody else had these
problems 10-12 years ago with their trucks, I decided to head off any problems that I knew were coming.
I pulled off & changed several things that I knew were good,,,,, but like me--- they're getting old and tired.

It seemed to run better & better, but still wasn't perfect.
I never could fix the hesitation and stumble when under acceleration from about 1,000 to 1300 rpm.
Without changing a $500. ECM, (that I wasn't going to do) I figured I'd just live with it.
Other than that,,, ya couldn't ask it to run any better.

It finally set a 300--301 intermitent miss code. I thought,,,, "Dog-gone-it, what now"?
It'd have to be the plug, coil, or injector on #1 cylinder.... and they're all new.

Starting at the bottom, I pulled the plug--- totally out of character, it is also the easiest one to get to.
Getting it out--- the wire thing that loops and goes over the electrode was GONE!
The engine ate it..... However it seems to have 'digested' it OK. No signs of lost compression or anything.

So I put in one OEM plug, crossed my fingers, said a few 'Anna-godda-da-vedas', and drove it.
If it ran any better when it was new---- I sure can't tell.

[high standard 40]

New parts do sometimes fail. Nothing that is man made is perfect. Glad you got a handle on it.

[jimlj]

Easiest plug to get to? That ain’t right. You need to smash your thumb with a hammer to make up for it.

[Recycled bullet]

I dislike removing the pieces of ceramic that fall into the cylinder through the spark plug hole when they break. I like to reset keep alive memory (transmission gearshift point and variable valve timing learning adaptations) after doing service, then rechecking fuel trim adaptations at idle and at 2500 rpm, anything plus or minus 10% is generally acceptable and verified the repair, that other components are also ok.

Glad you got it running well.

[Handloader109]

Hopefully hat baby will just keep chugging away. I bought my 2005 at 95k miles. Owner had supposedly changed plugs and coils just a few thousand miles earlier. I had put maybe 3 or 4k on it and it started missing, and I ended up changing all the plugs and it went away. Probably 50k miles later I had a miss when it was going up one long hill close to home. Only then. Thought I had bad transmission slip. Then finally threw missing code. And replaced all the coils with cheap ones. 40 or 50k later, I've slowly replaced a other set of coils with cheap ones and miss goes away. I'm down to 3 left and I really should change the plugs. 220,000, so roughly 110k on a set of plugs. Can't say anything bad about them either.

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[Winger Ed.]

[QUOTE=Handloader109;5594717]Hopefully hat baby will just keep chugging away. /QUOTE]

This late in the game, I figure it'll be the last truck I ever buy.

It's got the 5.4 with the variable cam phasers (and rocker arm/lifters) that give a lot of folks problems.
In my research, I found some real mechanics saying they work off of oil pressure, have real small passages,
and when people put the wrong oil in them, or don't change the oil often enough,
it trashes 'em out sooner than they would normally just wear out.

[Dave W.]

It's got the 5.4 with the variable cam phasers (and rocker arm/lifters) that give a lot of folks problems.
In my research, I found some real mechanics saying they work off of oil pressure, have real small passages,
and when people put the wrong oil in them, or don't change the oil often enough,
it trashes 'em out sooner than they would normally just wear out.

Yup, It is also best to use oil that meets the manufactures specs, does not have to be Motorcraft oil.

On the 5.4L's we have found it best to use Ford ignition coils and Ford spark plugs. I assume you torqued the spark plugs to the correct spec?

[Winger Ed.]

Uh-oh. I'm used to Alum. heads on motorcycles & boat engines, and snugged 'em like I always have.
I got the new generation one piece body ones, but never thought about putting a torque value on them.

I'm a big synthetic Castrol guy, but do use Motorcraft plugs & coils.
I'm used to old school 10-40 and such oil. I was a little apprehensive about 5-20 in the truck,
but figured they knew what they were doing and have always used that weight.

Same with the manual trans. I'm used to old 1/2 ton trucks that took a qt & 1/2 or so of 90-ish weight gear lube.
This thing calls for a specific numbered of auto. trans. fluid. I use what they say and under the Motorcraft label,
but this thing takes right at two gallons of it.

I change the trans. fluid at 30,000, and am fixing to do it again.
When I was doing that on the '02 Explorer, a neighbor ask why I bothered doing it.
I told him it didn't take very long , wasn't hard,
and is around $3,000 cheaper than waiting until the auto. trans needed a overhaul.

[farmbif]

when I bought my 2002 f150 2 valve 5.4 liter with 200,000+ miles on it knew what was wrong with it. coils and plugs, after much research and speaking to reputable shops I had very good results with Delphi coils $$120/8 vs $74 each for motorcraft and denso platinum plugs. price was excellent compared to local parts stores.

[jonp]

Yup, It is also best to use oil that meets the manufactures specs, does not have to be Motorcraft oil.

On the 5.4L's we have found it best to use Ford ignition coils and Ford spark plugs. I assume you torqued the spark plugs to the correct spec?

I disagree. As long as the plugs and coils are good quality aftermarket and not cheap Chinesium the should be fine much like the oil. I run Valvoline high milage syn blend in my vehicles.

[jonp]

Winger Ed, just be glad it wasn't that plug way in the back and it broke off while you were trying to change it out. Plugs in the 5.4 3v are notorious for welding themselves in place. Considering the age of the vehicle I'd be thinking about doing a timing job on it, replacing the plastic chain guides with metal ones, replace the oil pump with a high volume one and the water pump. I'd also strongly urge changing the cam phasors using either OEM ones or locking out the ones you have. Oil is also key with these engines, make sure to use quality with the correct grade.

Unfortunately, I've found out quite a bit about the 5.4 3v Triton over the last several years. There are a couple of forums online that have very good members and lots of knowledge much like here. This engines problems are all well known by now and everyone has gone down whatever paths you might already finding a fix and lot's of do's and don'ts.

[marvelshooter]

I was just on a tour in one of the National Park Service's red busses. The driver was telling us how Ford refurbished them with Triton 5.4 engines and how reliable and nice to drive they now are. Minutes later bam - one of the spark plugs blew right out of the head and we waited 2 hours for a spare bus. Apologies if too far off topic.

[William Yanda]

Not Ford, but my brother had his truck's oil changed at the dealer. They used the wrong oil and it developed a tic. No solution, so he asked the salesman what to do. The salesman, my other brother, how to handle it. The answer, "trade it". That was a couple of trucks back and I never heard the final outcome on the original truck..

[Hannibal]

Without going into great detail, had I known that the reason a weak fuel pump on fuel injected cars is a problem is because it allows the fuel to literally boil in the fuel line and pressure rails it would have saved me a lot of time looking for a suction leak.

Sometimes a little extra information is needed.

[MaryB]

#1 plug loss of ground strap raise a red flag for the intake is cracked and seeping enough water to rust it off... how mine started... #1 miss.

[Handloader109]

One thing I will say is that if it has issues with anything internal, the engine is trash. It isn't worth trying to repair. Oh, autolite plugs in mine, and I use Valvoline. Change the oil roughly every 15 to 20k miles. 5k isn't needed on anything.

[Hannibal]

Depends on your skill level and access to the proper tools. You can generally throw rings and inserts in something and replace the timing chain and guides and have the heads decked and get another 100K out of them with little more than standard maintenance.

Obviously if someone didn't believe in oil changes or even pulling a dipstick at least once a month none of this applies.

[Hannibal]

Ed, I'd keep an eye on that cylinder. Those electrodes typically don't fall off but I've seen them melted off several times. That and the lean mixture code would make me wonder if there's more going on than just a bad plug.

[firefly1957]

I had engine slip timing and the spark nock took the little hook off of three of my spark plugs before I got home (500 miles) to do the repairs .

My first computer controlled engine was a 1985 Oldsmobile Delta 88 307 cid. Under warranty it would stubble at a steady 55 MPH the dealer could not figure it out it was setting a rich burn code . I got a book from work on the cars and read up on everything about the early computer system did not get a lot of help . Then one night I opened the hood while it was running the sparkplug wires were bad that should have been the dealers first thing to look at but they wanted to use the cars computer to tell the problem . In use the O2 sensor would read the misfires and tell the carburetor to lean up a bit the car would be to lean and stumble at a steady speed it did not effect acceleration as that system did not read during those times .

A water leak around a sparkplug boot on a 2009 Mercury Grand Marquis was a similar issue in wet weather the ford dealer did not figure that one out either. I fixed that one with a silicone spray on sparkplug boot and the coils (one part) then at 80,000 miles found the leak when I changed the plugs and sealed them well with silicone dielectric grease .