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Got an 06 F-150 a couple months back with 80,000 miles on it. It has the Triton 5.4 engine and I'm getting what feels like a miss in it when the engine is lugged down in OD at 1200 to 1500 RPMs. Is this maybe 1 or more of the coil packs/spark plugs going bad? If I disengage the OD it seems to do OK at higher rpms. Second question is what does a tuneup on one of these engines run and when does that normally occur.
Thanks
Bob
You are on the right track with that motor. Common problem.
Very common to have the coil packs go bad. I've replaced several and are fairly easy to get to for the most part. I dont recall what year they went from the 2 piece back to the 1 piece spark plug, but if you have the 2 piece spark plug, get the rotunda tool to remove the broken spark plug......Make sure to use a good creeping oil like Kroil and allow them to sit in the galleys overnight after you remove the COPs. Slow and steady wins the race
Yes, you do most likely have a bad coil, classic symptom. A tune up, plugs and fuel filter would be timely soon. They say 100,000 but I wouldn't push the envelope.
As far as which coil you need a scan tool, if the check eng light is on then a dtc may lead to the # cyl.
I think 2008 were the smaller plugs.
it might be a bad coil pack or just corosion on the connector leads on/in the coilQuote:
Originally Posted by Boz330
I have a 99 f250 superdudy and the coil that most likley to go bad is the the ones right under the opening of the hood when open
I have fixed several coils by using a spark plug file 1/4 x 1/16 wide and filing lightly the top and bottom of the contact of the coil
blowing out the dust and reconecting the coil (with out removing the coil) just laying on top of the front of the engine/rad with a blanket under me --not the easiest thing to do
I came upon this method by buying one new coil and replacing one coil at a time and if it did not fix it replace it with the one next in line
some of the dignistic tools will not find the miss fire when sitting in idle with the machine pluged in (but you can physicaly feel it miss fire)
Used to find a bad injector or spark plug by using a spray bottle. A few spritzes on the headers and the one that doesn't evaporate as fast is probably the culprit. If you have manifolds it may not work.
Could be a coil. Could be a plug. Could be water or coolant intrusion into the spark plug tube. Could be fuel pressure. Could be an egr problem. Could be lots of things. As was suggested check DTCs with a scanner FIRST, even if the check money light isn't on.
If you decide to replace spark plugs, you're in for a special treat.
Gear
So I have heard. I wasn't planning on doing it myself. When I was young I helped rebuild an engine in a motel parking lot in New Orleans after a breakdown once and use to do all of my own maintenance. Not sure where the engine is even located anymore.Quote:
Originally Posted by geargnasher
Bob
right under the flux capacitorQuote:
Originally Posted by Boz330
Wait till you get a check engine light,they can determine which cylinder is the problem. I've a 2005, and about had a kaniption fit over $10 plugs, heck, the coils are almost cheaper than the plugs! I had bad miss show up a month after I bought this one, PO had replaced plugs only a couple of months before, one just quit. Good luck.
the dealer can monitor the cylinders without the check engine lite on to determine which cylinder it is. ( the graph will take a dip when it misses a beat ) yes most likely it is a coil but it's also due for plugs at that milage. yup those plugs are a pain but someone whose done a bunch should have the proper tool for the ones that brake.
By 100k, every fastener screw / bolt has corroded or had a build-up of grime. This is old school, but when I tried to replace the distributor cap on my 93 Ford F-150, one of the two mounting screws twisted off. Not one of my prouder moments, held it on until fixed with a couple of nylon wire ties.Quote:
Originally Posted by s mac
Ford says 100k plug change interval which in reality is far from optimal. Really using miles to determine when to service a vehicle is a poor way to do it, using engine hours is far better. I have had a misfire on a modular with a little under 60k miles that went away once new plugs are changed. Thus plug change intervals I use on my modular and all the ones I work on get plugs changed between 50k-60k miles unless the vehicle sees mostly highway miles. The COPs (Coil On Plug) do not go bad as quick as some people think. The plugs or the COP boots are the culprit more times than the coil. But guys think it is the coil so they change the plugs, and coils (which come with a new boot) which fixes the problem thus they figure a coil was bad when it was probably not.
Now for the bad news. Your 2006 has the 3V 5.4l which has the spark plugs that are prone to break off in the head during removal. Plus the plugs are close to $10 each. A Ford dealer may charge over $1000 for a plug change if a lot of plugs break. Ford has a TSB out on the plu gbreakage issue and there are several kits on the market to remove the broken plug piece from the head without removing the head. The breakage issue can be fixed by using an aftermarket one piece spark plug.
This video explains some of the issue with the 2 piece plugs and how the one piece plugs help to get rid of the breakage problem. As far as I know the Motorcraft replacement plugs for pre 08' 3V are still the 2 piece design.
https://www.youtube.com/watch?v=DoSh9O3XOho
Anyway. I would change the spark plugs and COP boots first and go from there. The COP boots can crack and have a poor seal over time which can be a cause of misfires. At 80k miles and 8+years old you are due for a spark plug change anyway. Misfires can sometimes be fickle and a slight misfire may not throw a DTC.
The switch to the one piece new plug design was during the 2008 model year. The earlier build dates have the old style and the later build dates got the new style. The switch occurred sometime around Nov 2007.(give or take a month) The new and old plug designs are NOT interchangeable. The new and old design have different colored COP boots from the factory.Quote:
Originally Posted by osteodoc08
New design top, old design bottom
http://i299.photobucket.com/albums/m...PlugBottom.jpg
Thanks a bunch guys. The knowledge base hear is just amazing and I knew I would get some good leads asking the question here.
Bob
There is a spring inside the boot that connects the coil to the plug. Misfires are commonly caused by junk growing on this spring and breaking circuit contact. I have fixed several misfires by simply swapping coil positions and applying dielectric grease to the plug boots where they seal. Might be worth a shot to try.