I recently posted a problem about my 1996 lincoln mark viii having a problem with "cylinder # 5 misfire". i changed spark plugs, wires, and the coil pack. I am still having the same problem. Also, when i changed the coil pack i went ahead and checked the new spark plug in #5 and it had turned black on the firing end and on the other end it had rust and some gunk on it. The gunky stuff could be the boot protectant, i don't know. Also i was told that the car was running rich. I am unsure if this helps any on finding a solution for it but I thought i would ask.

Check connection of wiring to Coil on Plug @ #2 and check connection of wiring to injector on #2. don-ohio (:^)

Possible causes - Faulty spark plug 5
- Clogged or faulty fuel injector 5
- Faulty ignition coil 5
- Fuel injector 5 harness is open or shorted
- Fuel injector 5 circuit poor electrical connection
- Ignition coil 5 harness is open or shorted
- Ignition coil 5 circuit poor electrical connection
- Insufficient cylinder 5 compression
- Incorrect fuel pressure
- Intake air leak

The P0305 code means that the cylinder 5 is misfiring or is randomly misfiring. Start by checking for intake leaks an if no leaks are found the next step is to replace the spark plugs on cylinder 5. If the problem persist more tests needs to be done to diagnose problem, see "Possible Causes



When is the code detected? Engine Cylinder 5 is Misfiring.


When a misfire occurs, engine speed will fluctuate. If the engine speed fluctuates enough to cause the Crankshaft Position (CKP) sensor signal to vary, the Engine Control Module (ECM) can determine that a misfire is occurring.

Go to youtube for instruction on testing the coil packs as well as the fuel system and compression!

change all plugs with proper ones - they are picky for some reason - do not change number or brand from original - coils were probably ok, - get some injector cleaner and run through it but check for exhaust leak at e g r tube - is a common over looked cause of misfire - a thing to keep in mind is misfire isn't always spark issue. hope I was of some help

It could be couple problems:
-Misfire. (Include bad injector, Coil, spark plug wire)
-Lost compression due to broken valves, cylinder wall and head or gasket.

Solution:
1 -Do compression test.
- If not with in specification (Too low) Need rebuild engine due to broken valve, blow out gasket or even broken cylinder wall.
-All cylinder has good compression:
Now need to check Spark plug, wire and all injector. Injector must be
with in specification (In Ohm) Follow its manual.

mai Lor

THis is the same that P0308 fault code when "check engine" light turn on. 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
Poor compression
Defective computer

Possible Solutions:
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.

Hope this helps; also keep in mind that your feedback is important and I'll appreciate your time and consideration if you leave some testimonial comment about this answer.

Thank you for using Fixya, and have a nice day

For the 1993 thru 1998 Lincoln Mark VIII 4.6L DOHC V8:

Firing Order:
1 - 3 - 7 - 2 - 6 - 5 - 4 - 8

Cylinders:
..........(back)...........
|...4...|..........|...8...|
|...3...|..........|...7...|
|...2...|..........|...6...|
|...1...|..........|...5...|
..........(front)

Coil Connections:
............................
|.1..6.|.........|.2..8.|
|.5..3.|.........|.7..4.|

Let me knowif this helped, or if you have additional information or questions. Feel Free to contact me at FixYa.com!

P0301 represents cylinder number 1. The most likely cause is  the coil boot that attaches on the bottom of the coil. Typically they crack from heat. The other concern could be the coil itself. If you find the boot cracked then replace all of them, they are available at most parts stores and it is good insurance. If you have more questions feel free to leave me a message in my profile, thanks.

The knocking can be from #5 cylinder which should be the front cylinder on the drivers side.
You should disconnect the negative battery cable for 10 minutes and see if the reader says the same thing after you restart the car.

If it does not cure the problem, it could be the coil pak for #5. The last thing would be a dirty or bad injector for #5. Hopefully the reader will show you fixed it.

The knock you refer to can easily be a balljoint or tierod end. If you are due for a frontend alignment those are parts which will be checked before an alignment can be done.

this pick should help.