AKlowriderZ71

iTrader: (22)

Misfire diagnostics are often "disabled" when tuning for a cam. By disabled, I mean that the thresholds for the DTC's are raised so high that the PCM will never set a P0305 to lead you to cylinder #5.(or other cylinders)

You'll need to change the tune if you want to use the PCM misfire diagnostics.

oakley6575

iTrader: (5)

Yea right now the misfire tables are maxed. I will set them back to stock and drive the truck during the week to see if I can narrow a cylinder down. The problem is that it only misses real bad after 90 miles or so.

If it was a true misfire, would I be able to see it on the wideband?

AKlowriderZ71

iTrader: (22)

Not always.

oakley6575

iTrader: (5)

Thanks, I will build a misfire config

1FastBrick

iTrader: (17)

How are you feeding that 408??? What Pump, Injectors, what Fuel Pressure??? Do you have a fuel pressure Gauge hooked into the fuel system???

oakley6575

iTrader: (5)

The only thing I've done to the fuel system is add a vacuum referenced fpr. I don't have a gauge inside the cab to see fuel pressure, only in the engine bay. Base pressue is set to 58psi with LS3 42lb injectors.

AKlowriderZ71

iTrader: (22)

Stock fuel pump?? For realz??

oakley6575

iTrader: (5)

Hell yea. haha AFR is solid at 0.87 lambda down the 1/4 mile.

1FastBrick

iTrader: (17)

X2... I beat it's killing that Biotch trying to keep up.

oakley6575

iTrader: (5)

Yea I bet it is too. I watch the wideband like a psycho but it still hasn't given up.