Helping a buddy of mine figure this out and its becoming a royal pain.
hes got a 2013 LML thats deleted. hes running tunes that i particularly care for but based on my logging, they are not the issue. Get to more on that later. Little back history.
Few months back, truck lost a piston. Wanted to do a build right then and there but i didnt have the time to fit it in within his time frame. So he went for a LKQ engine. it came with everything top to bottom but they swapped over injectors, put a new Cp4 in "just in case", reused alot of the stuff that came off his truck knowing its good. bascially stripped it down to a long block and put all the trucks original stuff back on this engine. they got it back together and about 100 miles in, the truck started developing a fuel knock from 1100rpm to 1500rpm, above that, quiet as can be. Also throws P12BA cyl 4 injector timing advanced. At this point, he called me and we started going over the truck. watched timing and rail pressure. actual follows commanded to a T and runs 10k rail at 1500rpm and 28mm3. fuel timing is from -1 to +4 from 1100-1500rpm and fluctuates depending on mm3 input. So no real smoking gun there. i told him to swap cyl 4 injector with cyl 8 to see if it followed.... he went and replaced all 8 injectors instead. Supposably it was fixed. truck went to cali and back towing and now knock is coming back as well as codes P2599, P12BA, P12B8.
I honestly feel its tune related but i figured id see anyone else has dealt with this first. truck doesnt haze, drives nice besides the knock, comes on boost quick, and doesnt indicate any other issues. Compression is 420psi across the board, no bad wires, and tune is set to "stock" but its a deleted stock im told does nothing other than turn off codes and what not. The tuner will not send me a 100% stock tune to flash in and test - again, another reason i dont like the tuning but i want to give a definitive reason before saying "go drop another 1k on tuning with someone else and lets see IF it fixes it".
if you guys need more data, let me know.
hes got a 2013 LML thats deleted. hes running tunes that i particularly care for but based on my logging, they are not the issue. Get to more on that later. Little back history.
Few months back, truck lost a piston. Wanted to do a build right then and there but i didnt have the time to fit it in within his time frame. So he went for a LKQ engine. it came with everything top to bottom but they swapped over injectors, put a new Cp4 in "just in case", reused alot of the stuff that came off his truck knowing its good. bascially stripped it down to a long block and put all the trucks original stuff back on this engine. they got it back together and about 100 miles in, the truck started developing a fuel knock from 1100rpm to 1500rpm, above that, quiet as can be. Also throws P12BA cyl 4 injector timing advanced. At this point, he called me and we started going over the truck. watched timing and rail pressure. actual follows commanded to a T and runs 10k rail at 1500rpm and 28mm3. fuel timing is from -1 to +4 from 1100-1500rpm and fluctuates depending on mm3 input. So no real smoking gun there. i told him to swap cyl 4 injector with cyl 8 to see if it followed.... he went and replaced all 8 injectors instead. Supposably it was fixed. truck went to cali and back towing and now knock is coming back as well as codes P2599, P12BA, P12B8.
I honestly feel its tune related but i figured id see anyone else has dealt with this first. truck doesnt haze, drives nice besides the knock, comes on boost quick, and doesnt indicate any other issues. Compression is 420psi across the board, no bad wires, and tune is set to "stock" but its a deleted stock im told does nothing other than turn off codes and what not. The tuner will not send me a 100% stock tune to flash in and test - again, another reason i dont like the tuning but i want to give a definitive reason before saying "go drop another 1k on tuning with someone else and lets see IF it fixes it".
if you guys need more data, let me know.
