Cylinder 8 misfire engine light

[BRAPPPP]

Hey I installed a roush supercharger and I am getting a cylinder 8 misfire code. The truck misfires when it is under load about 60% throttle id say. It doesn't misfire at Idle or light cruise. I replace coil pack, spark plugs, and all the wires look in good shape. Everyone I've talked to said it is highly unlikely an injector issue. Any ideas? I reflashed the tune also and that didn't help. I installed the kit maybe 2 months ago.

 

[MTF]

You could swap around #8 and #6 or #7injectors , see if the misfire follows.

I forget the firing order on the 6.2L
I think it's 1234 passenger side and 5678 on drivers side.

 

[BRAPPPP]

You could swap around 8 and 6 injectors , see if the misfire follows.

That was my next step... Could I also just unplug the injector and see if it still misfires ?

 

[MTF]

I wouldn't, you would run the risk of damaging the cylinder wall because of no fuel to wet the wall or rings.

 

[BRAPPPP]

I wouldn't, you would run the risk of damaging the cylinder wall because of no fuel to wet the wall or rings.

So the only way to test is to swap? Do you have any other suspicions other than injector ?

 

[MTF]

It's a little rare for an injector to fail. I would double and triple check the wire harnesses again. Check, clean the cam phaser plugs.

 

[BRAPPPP]

It's a little rare for an injector to fail. I would double and triple check the wire harnesses again. Check, clean the cam phaser plugs.

Yeah i took it to Ford and they said all the wire harnesses looked good. The coil pack was cracked at the top where it connects so they replaced that. But they didnt replace the plug that goes to the coil pack because they said it looked fine.... They did replace the plug that goes from the coil pack to the spark plug though, even though it looked fine just to be safe...

 

[MTF]

Did you try and swap two spark plug wires?
Other then that you have no choice but to bring it back to dealer.

 

[BRAPPPP]

Did you try and swap two spark plug wires?

I didn't try that. I replaced both spark plugs in cylinder 8 tho. Which spark plug wires should I swap?

 

[MTF]

All 8 spark plugs wires are the same, it doesn't matter.