Hi all,
I have been searching and trying to find a solution to my issues. Newbie warning of course... Well, new to HP Tuners and LS tuning but not new to EFI or racing. I used Accel DFI "back in the day as they say".
Anyway, I have taken a '02 Sliverado 0411 PCM (truck had a 4.8 in it) and converted the harness into a stand alone harness for my 1995 Camaro drag car. The car is equipped with a Powerglide so I have the transmission set to auto non electronic. The PCM has the HP Tuners 1 Bar SD OS installed on it. I have done a segment swap with a 2002 Silverado 5.3 for things like the cylinder volume, VE map, and most everything I found in the compare file that was highlighted green (other than the emissions stuff). I then used the LS3&LS7 file to get the proper injector data for the LS3 injectors I have installed. I have tried opening up a vacuum cap (small about 3/16 ID) so I could get some bypass air.
The issue is I can't get it to idle for more than 15 seconds prior to it just kind of running out of steam. It just kind of trails off and dies 1000, 800, 600, 400, 200 RPM then stops. I also cannot get it to do anything but instantly die if I touch the throttle (even VERY slowly).
I followed the big cam Idle tutorial on here (from another site). I *think* I got everything right but since I am a custom OS there are some differences between the article and my PCM. I also used Russ k's Idle config to plot the RAF and it is showing in the 20's right now but I assume that's because it is so FAT. The IAC steps are 200-300 sometimes as "low" as 160s. I tried setting the RAF to the numbers in the histogram but it won't even try to run. Starts then stalls right away. I am thinking it's too soon to be messing with the RAF number more than the article mentions.
The engine is PIG fat you can smell it really bad. I have tried pulling extra fuel out where it is currently idling (KPa and RPM). But then it simply won't run. It starts and then dies within a second or two. I also tried setting the PE KPa to a higher number so as not to get into PE at idle but even though the commanded A/F is showing better it still won't run and smells really fat.
I do not yet have a wideband O2 sensor but it's so fat I don't think it would help at this point. Bigger fish to fry as they say...
So some details on the combo:
5.3 stock bore and stroke
862 heads ported and reconfigured to an LS3 "style" combustion chamber. Flow ~ 280/210 at .700
10.75 - 1 ish. I don't have the math in front of me right now
Cam 240/256 113 +4 .629"/.604 Yes lots of cam for a 5.3 but its a strip only car with lots of rear gear...
Ported LS1 intake (for now)
Ported LS1 TB (I edited the IAC effective area to be the same as my 2000 TA). No epoxy in the IAC entrance
"Tune" File and some logs (sorry they are so short)
Camaro5.3BaseTune_Idle_Airflowls3 injectorspreadsheet.hpt
2019114LateDay2.hpl
2019114LateDay3.hpl
Maybe I should start from scratch with a 5.3 tune and add the LS3 injectors and such? I'm sure the tune file is a bit of a hot mess but I am trying to learn.
Thank you in advance for your time in trying to help!
Chris