I have a 97 F150 5.4L XLT, just replaced all plugs, then my check engine light came on and was bucking alottttt, barely any power goin up hills, had it scanned, it was a misfire on #3, changed the coil pack light went off, 3 days later same thing with bucking and light is back on, again had it scanned misfire on #6, changed coil pack on that, and now again light is on and misfire on #4, is this going to be an on going issue until I switch all the coil packs out and is there an easier way then taking off the fuel lines? or should I just take a match to it ????? Thanks, Pam

 

When you take the coils out for any service are you using silicone grease inside the boot tips?
Two reasons for using it is to help the boot find and slip onto the spark plug tip and to help seal out moisture preventing spark leakage at the tips.

 

Blue, yes each individual pack comes with its own grease packet. thanks for the reply, any other suggestions ?

 

Did you happen to wash the engine before you did the plugs?

 

no sir they did not wash it

 

Sometimes you uncover other issues you didnot think were there.
Just roll with it till their all solved.
Could be a lot worse.
Good luck.

 

Blue, so I should just keep changing the coil packs, and after all are changed if i'm still having the "buckin" "missing" then what ?

 

Get one new coil and roll it through all the cylinders allowing enough test drive time for each change to see when the miss is gone.
If there is another issue, your only out the cost of one coil and some work.
I'm sorry there isn't a surefire way (for you) to solve the issue other than to work on the problem or let a dealer test all the coils to pick out any with low output.
At this time i'm not sure you don't have more than one issue at the same time that's causing confusion.
These ignition coils and plugs are down in a well where you can't see what happens when the coil is set in place. If a boot hangs up on top of a plug it may work for awhile (jump the large gap) then begin to give trouble.
Carefull feel and some twisting back and forth of the boot/coil for resistance when setting down on the plug is required and not just jam it in place and bolt the coil down.
You must be sure the spring is not hanging up in the boot and not able to set down on the plug.
.
As well many have an issue with moisture infiltration during rain and off road operation because the boot seal at the top against the head is not good. I use the grease around the boot seal at the head as well and be sure the coil is seated level.
.
Other tricks I have used is silicone rubber seals 'on the spark plug' that allow a tight fit against the coil boot but takes a special tool to put the rings on the plugs after they are in and don't reccomend it for normal truck use.
Well more than you wanted to know but a little insight on what your working with.
Just that igniton work on these motors needs care and attention to some detail or you can have issues and have do it again to find problems.
Good luck.

 

Blue I was also told by a dealership, that if I only change 1 coil pack at a time that in time slowly ( every 30-50 miles ) another pack will go bad until all 8 packs r changed. Should've changed them all at the same time, Is this true?

 

Well I wouldn't agree with that statment because how would anyone know what the failure rate of any mutiple part like that would turn out to be because they all work independently even though they do the same job on different cylinders.
The service rep will tell you anything that covers a wide range and 'him-self', to that question and still be correct.
It's a lot like saying a stopped clock still has the right time twice a day.
A set of coils within the same age range always has the possibility to failure within a time period so it's all in how you want to look at it.
Any coil new or old can fail at any time same as a new set of tires.
A point that often is not included in the overall consideration by the customer is the dealer is somewhat bound to do the best type of job the first time so call backs are not occuring due to short cuts and guessing. They also have some warrenty obligation in the mix with the parts, you don't get with your work unless you can return a coil known to be faulty within a reasonable time period.
You have to make a decision as to how you will get the truck repaired and who will do it and what the costs are vs the benifits to you over the longer term and have it over with.
Sometimes there are issues an owner just cannot handle in a reasonable manner and time period and you have to make that decision or let the truck set.
This is why we go to doctors at times for medical issues aspirn does not fix.
Good luck.

 

lol thanx for all your help ! Pam