'98 Frontier-KA24DE-P0304-Cylinder 4 misfire code

[Bow]

I have a '98 Frontier XE 2WD regular cab ( KA24DE, 5 speed) and it recently started throwing a check engine light.

The OBDII code is P0304 Code - Cylinder #4 Misfire. I reset it, but it comes back within 70 to 100 miles.

I have changed:PlugsPlug WiresDistributor Cap and RotorFuel Filter

I also:Cleaned the throttle bodyChecked for manifold leak where the intake manifold meets the head with a can of carb cleanerChecked Injectors as per the FSM and they are workingCheck operation of the EGR valve

The oddest thing is that the ECU (using an Elmscan Scantool and a laptop) is showing the timing at idle to be at 10 degrees, but the timing light on the crank pulley is showing me 20 degrees.

While driving, I never feel the misfire.

Anyone have any advice?

OBDII sucks, I wish I could get my Consult reader to work with this ECU, there is an OBDII port and a Consult Port, but my Consult/Nissan Datascan will not connect to the ECU in my truck like it does in my '91 240sx.

Thanks

EDIT Friday Night UPDATE:Checked the fuel pressure tonightFuel pressure is good:43 psi at pump prime before engine start34 psi at idle43 psi at idle with vacuum line to FPR disconnected

UPDATE Saturday Night:I installed a new #1 O2 sensorTruck still threw a code.


Modified by Bow at 5:52 AM 10/16/2006

[Bow]

Bump

Anyone have any ideas?

[Bow]

One More Bump

[C-Kwik]

Kind of a tough one. My guess is that something unrelated may be causing the code to trigger. I believe misfires are detected as irregular rotations of the crank. You might want to get a hold of an FSM and run through the diagnostic procedure for that code.