Have an 01 f250 superduty with a 5.4 triton
Plugs done 1500 miles ago along with boots just tested and put in 4 new coils.
I have developed a miss and i feel like im parts chasing. The miss only shakes the cab when it goes to the lowest rpm for that gear. It is very subtle when it is in idle. I just cant figure out what is is some help would be greatly appreciated

 

If you feel the stumble in OD at light throttle, it is a faulty coil.
This failure won't set a code.
Only way to get a handle on it is to use a Scanner to look at the misfire monitors for each cylinder.
This will be found by using mode 6, test 53 on the Scanner.
Good luck.

 

It seems to clear up once it warms up after about 15 min of driving start stop which leads me to beileve something is stuck considering in jersey it been pretty cold anywhere from 10 to -13

 

This happened to me with my 5.4L. About pulled my hair out trying to find the problem. Seems that a injector wire plug was loose. The connections must be tight and be positive all the connectors for the injectors on fully plugged in. Just a place to check. I was just replaceing plugs but somehow a injector wire stayed loose in the process.

 

Resistance testing can confirm a coil is bad but
cannot confirm a coil is good

 

Let me expand on coil testing a bit.
A. If a coil is open either on it's primary side or secondary side, a resistance check would show this. However a failure like this will positively show up as a fail code for that coil/cylinder such that a check would be a moot point since it is already built into the program detection as a misfire code.
B. A 'shorted turns' winding is much more difficult to measure unless it is a dead short that would also be detected by the program as a misfire and coded as such the same as in A above.
.
A few or low number of shorted turns is a horse of a different color and difficult to measure with a common VOM meter.
The reasons why are three fold.
1. The change in DC resistance is small compared to the total amount of wire that it likely cannot be accurately judged with a common meter of either analogue or digital. A resistance bridge would have be used to see it and then you must still know the design spec tolerance for comparison.
2. Shorted turns will have a greater effect on output voltage because it has a great effect on the magnetic field built around the core.
Shorted turns essentially act as a magnetic short in action.
.
The computer and it's monitor software design takes care of this by measuring crank rotation time of the offending cylinder rather than trying to handle it on a resistance basis.
How it is recorded for us to see is by looking at the misfire records for all cylinders to see which one/ones has the high record counts...
Then there sometimes are heat caused intermittent that may not be measured with meter at a particular moment in time..
Best to use the tools the design offers for trouble shooting.
P030x codes for secondary issues.
P035x codes for primary side issues.
Mode 6 misfire records for those that do not set codes.
These cover PCM driver faults, harness, plugups, coil faults, spark plug and boot issues, plus cylinder mechanical faults.
Pretty clever overall diagnostic operations has been built into the design.
Good luck.

 

These are all great things to test. But if it gets you no where maybe look into is, is coolant getting into once cylinder and making it misfire untell the motor warms and and works that water out. Now that can be a head gasket or some other trase of coolant. Now it dosnt mean that it blown and will get your water and oil mixing. Its only leaking into one of the cylinders... Just another idea if its not ignition related

 

Thats what im thinking since i dont have a scanner i had my uncle ( who is a certified mechanic with35 years + in the industry) check it he changed one more coil. He then went on to say it is still there it just doesn't effect power. Which it doesn't it is only at idle and if it does miss any where else in the rpm range it clears itself out rather quickly if not i let of the gas then get back on and its gone which is why i am at wits end with this it has only become a nuisance some days it misses somedays it doesn't. I am honestly considering selling it and letting someone else deal with it

 

Respectfully, is sounds like proper diagnostics are not being done on this issue.
I don't hear about a Scanner being used to look at live and stored data.
You just cannot put stock in long time experience and not do the diagnostics properly.
A tech just out of school who uses the tools available vs one who tries to explain it away and try this and that, will always come out ahead on the problems.
Selling a vehicle to get out from under issues is one way, but it does not have to be that way.
I'm not trying to get your dander up but please consider this can be the basic problem underlying the reason you can't get results.
Good luck with it.

 

I just replaced 5 coils on my truck and still had a miss. Blamed it on everything possible just to find out one of the coils was bad. I put a good coil onto the plug in and put a good spark plug in it then grounded the spark plug and started the truck. I left the original spark plug in the engine for this test. It worked just like I hoped... the plug was not fireing. I changed that coil with a known good one and the miss went away. Just a thought.

 

A scanner tool was used when brought to the shop. I seem to think that I may have flooded a spark plug from the missfires, so I will probably check that next. If not I will test all the injectors and clean them

 

Your check engine light should show a error code that will tell you which spark plug is causing the miss.

 

A scanner will only read if its letting out a code. And if the cylinder has some coolant to cause a miss it wont through a code. Only sensors through codes. And i wouldnt get rid of the truck for the small reason. unless it is a head gasket only cus on theses motors there a big pain

 

A good 'Scanner', if used to look at the misfire monitors, will positivity ID a cylinder in trouble for 'any reason', whether a code is set or not.
A code 'reader' is useless for anything but codes that turn the CEL on.
You can see from this that the level to which you go in diagnostics determines whether you find or see the trouble reactions.
The system was designed to be able to see all the operating parameters if the right equipment is used and the user understands the data presentations.
Good luck.

 

This is what bg7 is referring to
Without this info you are throwing darts
Mode 6 second half of video
good luck keep us posted