knock @ 43 when uphill on freeway....WTF!!!

[yotabeater]

when i'm on the freeway, if there's even a slight incline, if i hit it under 3200 rpm and less than 25% throttle, the knock goes to 43 almost instantly. it wont accelerate at all when it does this. the turbo could spool all it wants, no acceleration. if i let completely off the gas and immediately floor it, sometimes it pulls through. usually i have to downshift and dump the clutch to make it up the slope. occasionally it even does this on flat ground, usually in 4th or 5th gear, when trying to slowly accelerate. i checked my fuel trim while it was @ 43 counts of knock, and it seemed fine. i even tried richening and leaning it out while it was knocking, and nothing made it stop. this is really pissing me off, and i can't figure out what it is. by the way, b16g @ 20 psi, 550's, walbro 255, afc, datalogger, fpr, etc. any help would be greatly appreciated. thanks.

 

[TURFNNSURF]

I was having the same problem, on the highway and also sometimes from a stop at a light. Never when I go WOT, only when I was using part throttle under 35%. I found that by lowering the settings on my AFC for Low Throttle between 1200 and 3000 RPM the part throttle knock went away. I also noticed that my fuel trims played a part in this. At my old settings my MID and HIGH trims were always a little rich 86% and 83% respectively. When I leaned out the AFC my MID and HIGH trims settled to 109% and 104% and the part throttle knock has not returned for almost a week now under the same driving conditions. My conclusion, was that my ECU was over compensating for theload it was seeing and rich condition with the old settings. When I got the settings closer to Stoich, the ECU didn't have to compensate as much under the same load.
I say try to lean the settings out a little again and give the ECU time to correct the fuel trims. Then see what happens. If all else fails have a wrench turning party, get a few buddies over, give them all 10, 12, 14mm wrenches and tell the to tighten any nut or bolt they see... Over the yrs some stuff vibrates loose. OH YEAH, check your motor mounts also.

Good luck