Mecha

This has happened twice in 2 years so its not a huge issue...


I am running 5* tune 89 octane performance tow tune with AFE CAI and 1 temp range colder spark plug.


I get the engine light on when I stomp on the gas to pass someone and rough running engine until I stop and restart truck.


The code I get is P0304, Cylinder number 4 misfire.


Attached is what I got with a web search for the code.


Anyone got any ideas what this could be caused by? I have not gotten ahold of 5* tuning yet.


Fault log report generated by Torque for Android
=================================================

Vehicle VIN: 1FTFW1ET8DKxxxxxxx
Vehicle Manufacturer: Ford
Vehicle Calibration ID: KGCTAC2.H32

Current Fault Log
------------------
ECU reports no current faults

Pending Fault Log
------------------
P0304: Cylinder 4 Misfire Detected

Historic Fault Log
------------------
ECU reports no historic faults
Other discovered fault codes
(possibly pending, current or manufacturer specific)
----------------------------------------------------
ECU reports no other fault codes logged

End of report.

bubbabud

Try running stock spark plugs gaped @ .030 to .032. No need or reason for colder plugs.

Mecha

its been 3 years on these plugs. why would i get this message and engine effects twice in last 2 years when i hammer the throttle to pass someone?

bubbabud

Because a carbon heavy cold plug will not fire reliably under heavy load. with the boost + the rich mixture .032 is about the max gap to fire reliably. If your plugs have been running 3 years they probably are not in the best shape depending on mileage. An intermittent miss fire wont always trigger a CEL but will store a pending code.

DaEnforcer

JESUS!

Some people should not be giving performance advice. It could be a couple things. First lets pull the plugs.

DaEnforcer

Also how many miles on the plugs.