Hello. Found out yesterday that no.8 cylinder is not firing. Read something about spark plugs popping out? 4.6 gt. Any truth to this?

 

on a 4.6? popping out prolly not. depending on year you may not be able to remove them without a special tool

 

It's on my wife's 2006 GT, trying to convince her it's got 90,000 miles,and needs a new more "powerful " engine.😎 But trying to find out if the plug issue is a problem we bought the car new.allways wanted to supercharge it.from the git,but was vetoed big time! If a rebuild is in order? Where should I look for power advice?

 

misfire is usually* a coil on those older 4.6's if it's a plug it's a nightmare, again, dependant on year

 

Spark plugs popping out was on the older generation mustangs (94-04).

could be a coil, could be plug (dead), can't tell you much more until you inspect both.

 

My brother showed me how to remove and replace those coil over things. No tools, no time, even on the side of the road, literally. He keeps a spare one or two in his trunk.

If you know #8 is an issue, remove it, remove another, swap, and see if the other cylinder is now dead. FWIW

 

good advice...should easily tell you if it is the Coil or the Plug.

Bill

 

ive read a few threads where a plug/plugs became loose but if I recall, it was after they were already swapped out, so its possible but not likely. as stated above, start simple. swap the 8 and 7 coil, check result. then swap 8 and 7 plug, check result. doing the plugs is a PITA and will test your patience. get some nickel anti-seize and the Lisle 65600 tool just for insurance and run a can or 2 of Chem-tool B12 thru a tank or 2 of gas. if needed, swap 8 and 7 injector, check result. if these don't get the cylinder firing then possible valve/piston damage, lets hope that's not the case. good luck