Rough idle/running issues. 2000 merc. mountaineer 5.0

[Josh41891]

Recently my 2000 mercury mountaineer 5.0 has been acting up. At an idle it will randomly start idLing rough and when I am driving at cruising speed around 50 mph if I hold my throttle at around 1500 rpms it starts surging and running rough. If I give it gas it jumps up to about 2000 rpms and smooths out. It did trigger two codes that said random misfires on the 5th cylinder. I recently replaced plugs and wires and it has a good spark and compression. Any tips would be apprecoated.

 

[gmanpaint]

I would say it is most likely one (or more) of the plugs and wires you replaced.

You can test it by removing one wire at a time, and see if the engine changes at all with the wire off. If it changes when you remove a wire, it's not that wire/plug. If no change happens, it's that wire/plug that might be the issue.

Free test, just be careful not to shock yourself doing this.

 

[Josh41891]

Yeah. Like I said I just recently put new plugs and wires in it. The scanner said 2 different codes were a misfire on cylinder 5. So I checked that plug and wire and they look fine.