Scan Code: P306

[rickymac]

RV running fine, but just received engine light and ran scan, code was P306, miss fire on cylinder 6. I have started reading up on this problem. I would appreciate any recommendations from the group.


RV is a 2014 Thor Windsport 34f, 64000 miles.


If I need to put in for repair, I live 150 miles from Montgomery and can take RV to Stivers Ford.

[javelin]

Just a WAG...replace the coil pak on #6 cylinder.....and if still a problem then drive to the dealer. I am sure there are V10 experts on the forum that might have better advice.

[Thehobe1]

You should probably start with removing the spark plug and just replacing it if you don't have the means to test it (i.e. color, cracking insulator etc.) Next would be the ignition coil(s); probably have to switch or replace for any confirmation. It could also be the air/fuel mixture sensor, Oxygen sensor (s), EGR valve, the catalytic converter, leaking air hose after the air/fuel sensor etc. If it runs fine, get a OBDII checker that can graph oxygen sensor status (~$50 for one that can do this).

[lug]

A cracked plug will give you that code. Don't forget to replace the boot and use dielectric grease. The boot will get a carbon trail from the high energy being discharged through the crack. My #3 plug failed, 3.5L EcoBoost, at 62,000.

[Diemaster]

first of all, the codes are a letter then 4 digits, not 3. P = power train, U= network etc...

2nd, anything could create a misfire. lack of compression IE a valve stuck open, fuel injector not injecting or open circuit, spark plug not firing, coil circuits open, etc. Yes, the plug is the easiest to check first but you should figure if your getting fuel also.

[Sweetbriar]

1. Clear the code and see if it comes back.
2. If it returns swap the coil pack and power lead with one of the other nine cylinders before doing a blind replacement.
3. If the code changes the coil pack is the problem. If the same code returns replace the spark plug.
4. If the same code still returns make an appointment with a service tech.

Your warranty has long since expired so take the coach anywhere you feel confident with or even consider a mobile tech if any are available in your area. V10's have been around 20 years so the knowledge base beyond Ford is pretty expansive.

[Lt Keefer]

Clear the code and see how quick it comes back, if it does at all. Then swap the coil pack with another cylinder. If code moves, replace coil pack. If it doesn't, replace spark plug. If you still get the code you need further diagnostic tests that are above my pay grade. You could watch some videos from South Main Auto or Pinehollow to get an idea on further diagnostics. They are both on Youtube. Good luck.