Just got a new code p0308 (cylider 8 misfire); anybody know where the coil pack I need to replace is located on the 5.4 L or any other ideas would be appreciated. I've got 69K miles on my 06 fx4 so I guess it's getting close to time to replace plugs. Just want to know where coil pack 8 is located for now tho. Thanks
I do not have nor have not worked on a 5.4, but the way I understand is that the 5.4 has a COP system or Coil Over Plug. So there is one coil for each plug. 8th cylinder should be drivers side rear cylinder.
It could be from a bad coil, sparkplug or a sticky injector. Most likely the plug or coil though. Remember, start with the cheap stuff first!
Found a small leak in my exhaust, could this cause that code to come up? My truck runs fine until I go to pass or get on the interstate then it kinda stutters but eventually goes on. Bad gas maybe??? I have been running 89 & 93 octane but just recently switched to 87 cause of prices. No problems when I was running the higher octane so that could be the problem I guess?
A P0308 code means that the the car's computer has detected that one of the engine's cylinders is not firing properly. In this case it's cylinder #8.
Symptoms may include:
the engine may be harder to start
the engine may stumble / stumble, and/or hesitate
other symptoms may also be present
A code P0308 may mean that one or more of the following has happened:
Faulty spark plug or wire
Faulty coil (pack)
Faulty oxygen sensor(s)
Faulty fuel injector
Burned exhaust valve
Faulty catalytic converter(s)
Running out of fuel
If there are no symptoms, the simplest thing to do is to reset the code and see if it comes back.
If there are symptoms such as the engine is stumbling or hesitating, check all wiring and connectors that lead to the cylinders (i.e. spark plugs). Depending on how long the ignition components have been in the car, it may be a good idea to replace them as part of your regular maintenance schedule. I would suggest spark plugs, spark plug wires, distributor cap, and rotor (if applicable). Otherwise, check the coils (a.k.a. coil packs). In some cases, the catalytic converter has gone bad. If you smell rotten eggs in the exhaust, your cat converter needs to be replaced. I've also heard in other cases the problems were faulty fuel injectors.
maybe this will help get you started.
have you looked to see where the exhaust leak is? if so, is it pre or post cat?
something else you can try is moving the coil from cylinder 8 to cylinder 7. if the code comes back on cylinder 8, then the coil is not the problem. if it comes back on cylinder 7, then the coil is bad.
#8 Cyl. is on the drivers side all the way in the rear. If you are going to replace the sparkplug, be very carefull, it could be stuck or even break.
If you are replacing the plug, loosen it first 1/8th turn and spray some penetrating oil in the valley and let it sit for about 15- 20 min. then rock the plug back and forth till it is out. Good luck.