I have a 98 5.4 with number 4 misfiring. I'm not new to the fact that this is common. Did all normal steps to diagnose(new cop, plug, check hole ect).I have went as far as replacing the entire wiring harness, and still have the misfire. I have an edge programmer that informs me of all codes and all I get is #4 misfire. Anybody else had this issue before? Now all of this started when I changed my passenger side valve cover gasket. Any input helps!!

 

Switch injectors with another cylinder.

 

I will try that.

 

If that isn't it, you may want to do a compression test.

A thought - pull the valve cover and make sure the follower didn't slip off or something.

 

that I have done and it peaks out around 95. Now inform of what the follower would be?.

 

95 doesn't sound good. Pull all the plugs and compare the cylinders.

The follower is to an OHC what a rocker arm and lifter would be for an OHV.

 

So finally found the problem. Pulled the injector back off and the cap on the end had a hairline crack on it, so replaced it and ended it all. Thanks guys for all the input

 

Glad you found the problem. Thanks for letting us know.