2000 5.4l f150 176,000 miles, miss fire cylinder 1 CEL. The truck seems to be running perfectly at temp. But when it hasn't been started in a day it seems it has a miss for the first 30 seconds then it runs perfectly. changed plugs, coil packs, injectors, and performed a compression test that showed good 200psi.
still firing the same check engine light. Im thinking wiring or computer. now i did have the intake manifold replaced 2 years ago so maybe that could have some thing to do with it to. I also have the stock mod cold air intake with the 3in pvc into the wheel well and k&n high flow filter. Ive heard other thing to like pcv valve or other egr components. Any way can EGR system throw a missfire code. Can the computer or wiring be failing, is that common? just throwing this one out there because of the cold air mod. Mass air flow?
My last question is, im thinking of taking it to ford to put it on their computer is the dealer ship computer a good resource or will i be wasting my $100.
ps sorry for the miss spelling and punctuation hope yall understand and thanks for your response

 

Have you cked for vac. leaks ? No coolant or water around coil boot ?

 

Sorry to ask but is the code a P0301, so we are sure?
With new coils and presumably boots and plugs, did you use dielectric grease inside the boot tips to be sure the boots slip onto the plug and sure the spring is not retracted up inside the boot?
If all is good the only thing left is the harenss back to the PCM and the cylinder 1 solidstate switchs in the PCM.
The way to test for this is use an Ohm meter set to scale for reading 10,000 ohms on one of the scales.
Look back on the lead going back to the PCM switch for the coil and the injector to ground but not on the 12 volt side.
What you should read is about 10,000 +/- .
If much higher or very low, the PCM switch is faulty.
This requires a PCM replacement and reflash for PATS and two keys.
At this moment it's all I can get out of what you report.
If a coil or injector plug is at fault you would need to troubleshoot for it.
You really did not have to do a mass replacement of parts for a single cylinder issue, for the expense of it.
EGR is not the cause of a single cylinder hard fault..
Good luck.

 

+1 to Bluegrass's question about replacing the boots and using dialectric grease.

I'd put a test light on the ground side of the cyl #1 coil and another test light on the ground side of the cyl #1 injector and see if the test lights blink off and on during that first 30 seconds of operation. If they do, the two wires going to the PCM and the drivers within the PCM are pulling those circuits to ground okay.

 

Thanks for the replies.Yes sir the code is P0301 and the parts I already had due to my recent routine spark plug change, I had extra coils and plugs found a deal online for 10 motorcraft part# specific plugs $10, 10 coil pack $90 When we did the change out we used the dielectric grease and all new components for the coils and plugs. Do you all know where to get some good test lights online or local shops. now my question is can my $95 at the dealership tell me what is wrong so I can have fun fixing it. This isn't a joke every time my lariat brakes I'm psyched oh and ps the coil packs are from a company called protech I did swap cylinder 1s coil out 3 time with the old motorcraft ones to see if the coils were bad and still cylinder 1 Cel comes up. Just for fun were is the pcm located

 

I fixed a similar issue once before on a company truck. The owner replaced everything like you did, even went to the dealer with no luck. The miss would disappear when he got there. Turned out the wires going to the COP were broken inside the insulation right by the connector. I got lucky and noticed the wire felt weak when I was plugging it in. I simply found the break with an ohm meter and cut and spliced it back together. That was two years ago and it hasn't missed a beat since.

Oh, I've also had brand new plugs that didn't work right out of the box. Try swapping that around too.