Johnny09

Ok background, 2009 Silverado 4.8 - recent swap to 6.0L, ljms stage 1 turbo cam, 76mm turbo, injector dynamics 92lb Injectors and single walbro 450 running stock fuel lines/rail.

4l80 swap, for what it's worth.

Problem, I began tuning and went fine up until I tried wot, then it started burping madly at 3500 rpm, won't go past it. Hp tuner scan shows bank 1 o2 sensor is measureing wave form (14.7 ish) and bank two is clearly rich. (At part throttle o2 sensors read the same).

I sprayed carb clenaer while idling idling hoping for a leak, nothing.. ?

Afr reading bounces all over the place, reading the mixed exhaust. Please, any theory's would be welcomed!??

FFDP

iTrader: (2)

You could swap sensors side to side to see if it moves, then you'd likely have a bad o2 sensor.

It could also be worth it to log misfire on all cylinders to make sure bank 1 isn't showing any misfire and causing the o2 sensors to read funny. Tunes and logs are helpful to see too.

Atomic

iTrader: (42)

Massive misfires on that side, probably a burned plug wire(s).

Johnny09

ok i swapped o2 sensors, same deal, bank 1 runs lean at WOT. so its not the sensor and its definitely bank 1 running lean?

leaks? i tried a carb cleaner spray at all intake ports and vaccum lines, no idle change.

foul plug? they are brand new but i havent pulled them yet, thats next on my list, maybe find one thats lean.. they are new aftermarket wires... some random brand, possibly faulty?

any ideas guys? diagnosis suggestions?

log and tune attached for those interested,
I am running in MAF only mode?? i was attempting to go maf only at first? not sure if this could be an issue?

Last Call

iTrader: (4)

a variance in bank-to-bank fueling would not be a result of the MAF-only tune.

I think its a misfire which would show as lean from the cylinder NOT burning the air charge. Check the wires and pull the plugs to see how they look.

FFDP

iTrader: (2)

Kinda looks like once you reach past 130kpa everytime it starts doing something, both o2 sensors are close and then bank one is lean from likely a misfire.

You really need to be logging knock retard as well, that is a 100% must.

Other random tid bits, disable COT and the cat test in the engine diag tab. You want those disabled forever because of your setup, it'll also prevent them from being active while you tune. With them enable it might go into COT or do a cat diag test and start throwing your data off.

smokeshow

iTrader: (16)

Clear long term fuel trims, just for fun.

Atomic

iTrader: (42)

How much do you want to bet you have a bad wire or plug? Even if they are new the wire is burned or plug is cracked or fouled.

Johnny09

I took the plugs out, nothing jumped out at me... aside from one of the plug wires broke as I pulled it off the plug. It was a rock auto plug wire, I thought it would be better cuz it was 10mm, well it appeared cheap, I'll need a new one, at least. I'll attach the picture of the plugs, maybe you guys can spot something I can't. If anything # 5 (third one from the left ) might be a bit whiter porcelain than the others ? Would misfire plug be obvious? 1 top, then 3 below, then 5 then 7

Johnny09

Plug gap was set at .28 btw...