Mail order tune help idle stalling

[Bigbeave1]

Hi im new to tuning have a 99 5.3 swap in my 84 cutlass 2.5 exhaust tss 216/220 500. lift cam 2800 stall 4l603 mail order tune here is the issue car starts and runs when up to temp if you crack the throttle in park it stalls also have to feather it in gear a bit other than that it runs good I was wondering if there is a small change I can handle like I said new to the tuning end of it and want to learn I did send the data logs back to the tuner waiting for the changes but figure try here first or get some input with whats wrong
thank you

[5FDP]

It needs a lot of help still. It's lean just about everywhere according to the fuel trims, the airflow model needs a ton of work to fix that. Then correcting the idle will be a lot easier once that the airflow model is correct.


I will let you know ahead of time that you do not have enough fuel injector to even come close to be safe once you start going wide open throttle. 1999 got the smaller injectors they offered at 21-22lb/hr and likely not even the 25lb/hr injectors they used in 2000-2007 model would be enough with a cammed 5.3. Before you get too far you really need to upgrade those to like some 8.1 Vortec injectors so you only have to tune this thing once.

Get a wideband o2 sensor too, it's a must here.