I have a 2002 f150 with a 5.4 and it feels like its missing. it does this below 2000 rpms and when its cold primarily. Occasionally it will act like its missing when its warm but not too often. please help me diagnose this. Any help is appreciated. oh and it has no CELs

 

I would start by doing some basic maintenance. Clean the IAC valve, clean the MAF sensor and change the fuel filter. Go from there. That should cost you under $20 and take little time. How many miles on your plugs and cop's?

 

Likely a faulty coil on one cylinder.
When they act that way no code is set because it's not a hard fault.
Good luck.

 

ive cleaned the iac the maf and changed the fuel filter all in the last week. how do i check for a faulty cop?

 

First, a missing condition is not an air meter, an IAC, or a fuel filter.
It's a single cylinder missing according to a specific set of conditions that comes and goes as you drive..
The only two ways are to either sub a new coil by rotating it through each cylinder and testing or have a dealer 'stress' test all the coils for 'low' output.
Since it is not a hard fault the PCM will not set a code for you to see on a non existant permant type fault. If it did you would see a code for that cylinder so there would be no question.
The fault has to be either a short or an open to be detected or a total plug/boot failure.
Good luck.

 

How many miles on your spark plugs and what brand are they?

 

I dont know the person i bought it from said that they had been changed and i bought it with 120k on the odometer and now has 130k. After school i got in and drove home and it missed. Then when i got in to go to work it ran fine like nothing was wrong