DTC FRZF P0308
FEUL SYS 1 CL
FEUL SYS 2 N/A
LOAD PCT 90.6
ETC (*F) 192
SHRTFT 1% -0.8
LONGFT 1% 3.1
SHRTFT 2% -2.3
LONGFT 2% 1.6
RPM (/MIN) 1543
VSS (MPH) 30
SPARK ADV 29
IAT(F) 109
MAF (LB/MIN) 5.085
TP (%) 24.7
O2B1S1 (V) 0.700
SHRT F1B1S1% -3.1
O2B1S2 (V) 0.710
O2B3S1 (V) 0.775
SHRTFTB3S1 -4.7
O2B3S2 (V) 0.205
RUN TM (SEC) 78
FRP (PSI) 37.8
EVAP PCT(%) 41.2
FLI (%) 44.7
WARM UPS 0
CLR DIST (MILES) 14
EVAP VP (in H2O) -0.310
Baro (in Hg) 24.8
CATEMP11 1171.04
CATEMP21 1171.04
VPWR (V) 13.635
Load ABS (%) 48.9
EQ Rat 0.999
TPR (%) 12.5
AAT (F) 86
TP B (%) 37.6
APP D (%) 30.2
APP e (%) 38.4
APP F (%) 26.7
TAC Pct (%) 19.6
Sorry. My training and experience ended before 1980. Does 3V mean Three 2V carbs (tri-power)? I have owned 3 of those. 1963 Pontiac Bonneville 421cu in 390hp tri-power. 1960 Chevrolet Impala 348 cu in 330hp Tri-power. 1963 Ford Galaxie Super High Performance 406cu in 405hp tri power.
P0308 Misfire cylinder #8
1543 rpm
30mph
engine coolant temperature 192 degrees
fuel rail pressure 37.8psi . . . normal for this engine
the engine was running for 78 seconds, when the dtc was generated
all fuel trims within normal parameters . . . at the time of the freeze frame
Based on what you gave us, it might be time for an ignition tune-up . . . it’s due every 60K
Some words of advice
After you remove the coils, blow out all the dirt . . . there WILL be dirt . . . out of all the spark plug tubes with an air nozzle
SOAK the plugs with penetrant and let it work its way down the threads . . . that means letting them soak for at least 15 minutes, if not longer. you will thank me later
When it’s time to remove them, work them back and forth SLOWLY, as you remove them They will howl in protest . . . this is the carbon buildup
It is quite possible a coil or two are also misbehaving . . . this is quite common with the Triton 3 valve engine
And if a plug does break, that is also very common, UNLESS you soak the plugs as I’ve already mentioned, and have the patience to remove them slowly.
When you get them out, the plugs will be black . . . this is the carbon I mentioned
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You’ve either got a loose breather hose from the valve cover to the air cleaner housing/duct or your Mass Air Flow sensor is underreporting. But neither of those will cause a misfire on cylinder #8. More than likely a bad spark plug/ignition coil.
Good luck removing that spark plug. Do a google search for Ford Triton 3 Valve spark plugs.
I’ve had good luck removing those spark plugs with a 3/8" impact wrench on a hot engine.
+1 to @asemaster on the impact wrench on the plugs.
Did that on a 2007 3 valve 4.6 liter V8 (one of the bad ones for broken plugs) after seeing a couple of YouTube videos. Works like a charm