having trouble getting control of SD idle fuel

[0rion]

Idling the car in SD. I have an adder or something I can't find to get it to command what I want it to. Car cold starts rich and then gradually builds to lean but on a hot idle it'll start falling. I currently have the entire OLFA table set to 1 trying to figure out where the richer commanded is coming from on cold starts. I've zero'd the enrichment tables at operating temps trying to find it with no luck. What am I missing? I know I have some tables I have to go back and return to stock but wanted to find the one I'm missing first. Any ideas? Car idles and drives decent but I can get it much better if I can get control of the OL fueling.

car
00 T/A
6L (LQ4)swap
tsp 233/239 on a 112
3500 stall
factory 243 heads
LS1 intake/stock throttle body
12580426 flex fuel injectors

[Lakegoat]

Go to Engine Diagnostics---Airflow--Mass airflow sensor and set to fail at 0 or 1, not 14,000. It is not in SD mode. Make sure that you have all 4 injector data charts up to date for those injectors.

[Lakegoat]

Each time that you do a write calibration, make sure and open scanner and reset fuel trims. Then let it run a few minutes before you start changing numbers.

[Lakegoat]

What is Glowshift on your Channels? If that is afr wideband, it is showing LEAN

[0rion]

Yeah....glowshift is the wideband. It is up and down depending on ect temps.....mostly lean but cold starts it'll command 13.x and wideband will be high 11's and low 12's. Only the idle area is SD.

I think I may have found one of my issues. I just did another compare to the LQ4 truck tune and it looks like I didn't copy those injector tables over. I could've swore that I did that.

edit:
Just looked back at my notes and found where I copied those tables over.....only the tables hadn't been changed so evidently I didn't save it or something. Seems about par for the course....just creating my own troubles haha

[Alvin]

I've had lots of issues out of those widebands. I've never seen one read correct.. just a FYI

[0rion]

I've had lots of issues out of those widebands. I've never seen one read correct.. just a FYI

Thanks. It's my neighbors car. I'll pass the info along to him. I run an LC1 in my car and told him that before he bought his. Probably went glowshift because it was cheaper would be my guess.

[0rion]

I've made a tad bit of progress on the car but feel like I'm just missing something somewhere. Still have the rich start up for the first minute or so then a period of surging until it goes to closed loop and after that it starts and runs perfect. Do I need to start over with the idle air? I pulled some air out of the p/n base below 104 just to see if I could get a positive change out of it but no luck. I can't figure out why it has that 13:1 on start up even though I'm commanding 14.6. I don't really think the fueling is my root issue but would like for it to do what I command so I know I have control of it. My gut tells me it's idle air so I may start over with that base table. Any suggestions are welcomed. It feels like I'm chasing my tail and I also feel like I'm missing something basic or I've made a change somewhere that's created this issue. I pulled a ton of fuel out of the ve in the idle range but I've seen no change in afr.

[kevin87turbot]

It's actually commanding 14.63 AF ratio throughout your datalog...other than the during cranking of course.
I would just do an SD tune on this one if it were mine. Just change the MAF high fail freq to 0.
If you do that, you'll just need to copy the High Octane Spark table over the Low Octane.
You might also do the Enhanced SD/RTT mode. This will eliminate the secondary VE table for you.

After doing all of that, do a write entire, and make sure you clear the long term fuel trims between tuning sessions.

Also need to go to the trans diag tab and disable the Max Line Pressure DTC's.

After doing all of this, be sure to add the IAT and STFT's to your scanner and do another datalog for us.