replaced the coil on my 2006 Ford Ranger V-6 3.0L and no more misfire on cylinder #5.
the old coil was bad.

when I get on the highway and try to get to 70mph getting a lot of clattering sounds from the valves, no engine codes or misfires.

I changed the cylinder heads 60K miles ago.
my question is could the rockers be loose?

and i have driven it about 300 miles and the clattering seems to not be as bad

it only happens when i stump and the gas pedal to get to highway speed, someone ask what type of fuel i was using and i was using the cheap stuff. a mechanic said it could be the fuel, I'm running higher level fuel and the clattering seems to have gone away.

i cleared the codes after the coil change and after 300 miles no engine light or codes on my code reader .

something about the low octane fuel wasn't burning properly causing the clattering sound

And Thank you for you help