My F150, 1997, 110,000 miles feels like a miss fire around 40MPH. I have replaced spark plugs and wires. Not sure if it is ignition problem or a transmission problem. Today she missed so bad it triggered a check engine light.

 

Have the code pulled to find out what is wrong. If it is a missfire, pull that plug wire, make sure there is no water build up in the plug hole, then pull the plug to examine for and carbon tracks.

 

cel will blink while it is missfiring so it sounds like you don't have a miss. maybe a bad/dirty injector.

go get the code read. and let us know what it is.