I'm brand new to tuning, literally my first tune.. and have been reading for a while...I built my first tune (I'm sure there is a bunch of improvements needed) and i cant get the truck to fire.... Truck is a 01 4.8 with a 212/216 low lift cam, headers, tbss intake with flexfuel injectors, and 90mm throttle body. I dove head first into this and really should've started with a stock truck lol... Anyways i cant get it to fire in my tune... maybe someone will know exactly what's going on and its a simple mistake... Or maybe i need to start over ( i hope not).
BTW i have converted the injectors over from gen3 to gen4 and have attached the spreadsheet incase someone else needs it. (disclaimer i didn't make the spreadsheet)
what do you mean not fire like no crank/no start? or it fires over but dies right away?
if its the 2nd one then it sounds like you need more base running airflow - add 3 g/s to the braf chart and 2 g/s to the iac park position airflow and see if it gets any better and if so then you'll just need to work at it - you have a bigger throttle body and camshaft its going to need more air now - there is a thread on here for idle tuning - get yourself a wideband o2 sensor for wot tuning and for idle/part throttle if you want but i just use fuel trims (shoot for -5% ltft) https://forum.hptuners.com/showthrea...e-(w-pictures)
fix that idle rpm also it should go from high and smoothly taper down to what you want for idle - it shouldnt go down then up and down again
the added airflow will only help if it cranks and fires over but will stall or you have to hold the pedal to the floor to keep it running - thats usually a sign of not enough airflow but if your not getting it to crank at all then you have other issues like power to the starter, the starter itself, ign switch along those lines