ilike55s

Howdy to all,,,My 2000 5.4 F150 has got me buggered with what WAS a low speed ignition miss. Sometimes engine would miss from idle to bout 15 MPH. was not continous but just come and go. It has never stored a code or check engine light so putting a reader on it at Oreilly's would not tell us nothing. Issue has progressed to where it is now doing it at erratic speeds up to 70 MPH.
It acts as if you cut the key off and back on. I know what a spark plug or coil or wire miss sounds and feels like,,is why I think it is an ignition cutting out,,,but what could THAT be,,???
Can anybody help and show me the way,,???

NFortin1966

I would first perform an inspection. Pull the coils to see if the boots are wet with oil or coolant, or show signs of swelling or being brittle, check the coils themselves for heat stress or cracking. Look down the spark plug holes to see if there is any moisture inside like coolant or oil as it may not have reach the boots yet. All this can cause intermittent misfires which may not set codes as it may not be consistent enough to do so. Next pull the plugs and look at how they are and check the gap, check for carbon streaking on the porcelain as this can cause the power of the spark to run up the carbon instead of jumping the gap to create the spark.

SquareHeadLights

Could also be the anti theft system, my 02 f150 would act like it was missing at times and the security light would flicker at the same time. Did some research and found it to be a common problem. Check the dash when u feel the miss and see if the security light is flickering when it happens.

ilike55s

Hey NFortin and SquareHeadLights,,,many thanks for your suggestions,,but I'm afraid I did not explain very well how the trk is acting. I said a "miss" but is really like you cut the key off of a second and it loses all power for an instant. Sometimes, it will do this several times, one right after another and other times just do it just once every 10 minutes. Issue is getting worse as it now doing this up to 70 MPH
I'm gettin real leery bout drivin the trk,,thinkin engine is fixin to quit altogether and leave me stranded somewhere,,,!!!
Could it possibly be the ECM,??