Please help with stalling issue

[Kzhurley]

Hello I have an issue of stalling about everytime i come to a stop. It makes it pretty hard to get any good data to get my ve sorted out.

My setup is as follows:
lq9 shortblock with sloppy stage 2 228/[email protected] 112 lsa
LY6 rec port heads
ls3 intake
12631214 flex fuel injectors
DBC truck throttle body adapted to the ls3 intake
headers and 4in single exhaust
tko600 trans
ls2? i think 3-wire maf (disabled to tune ve)
p59 ecm from 2005 express with drivers for iac and tps dbc..

(note on pcm, I had originally os swapped it to 12592618, a 2005ish export 5.7l vortec tune as i was going to use on a 4x sbc conversion. that had other issues so i ended up segment swapping a 6.0l dbw and manual trans tune and turned off the dbw stuff in the systems tab. I also found a 2003 6.0l dbc tune and copied all the settings I could in the electronic throttle tab. I did not go back to the 2005 express dbc os 12587811 since i was unable to find a manual trans segment for that os)

I dont know if possibly I created a bunch of issues by doing all the os swapping stuff.

I've played around with the throttle follower and cracker and braf some but it didnt seem to do much below like 1000rpm. Car will start and idle nice and the iac does operate as it should seems like.

Would someone mind maybe taking a look at the tune and log to see if anything stands out?

camaro idle1.hpt25-07-17 19-23-45stall.hpl

The stall happens around 1:00 into the short run.

Thanks for your time

[horsepowerguru427]

I dont have data for those injectors, but all the necessary parameters were altered, so I'll go on the assumption that theyre correct for now. Not much underspeed spark to try and save it, I added some for you. Timing tables look bad around idle and all over. Huge valleys and dips its has to overcome if it hits those areas. I smoothed those out for you as well based on stock timing tables and what changes you had.

No guarantees, but heres an altered file....

[RDF1]

Are you sure of the injector part number?
That 12631214 is a crank sprocket.

[Alvin]

IMHO desired idle speed is too low. I'd go 800 since you are a manual. if it was an auto maybe it would do ok at 700.

I'd also encourage using a wideband to get the VE fully flushed out as the fuel trims move to slow to capture how rich or lean it might be in decel or idle dip areas. Use fuel trims as final say.. but the first several passes should be done with a wideband.

[dhoagland]

Not sure if this might help, and I'd also like to know what determines Desired idle RPM (I will search later but dont have time right now.

While looking at his stall condition I noticed when he was dropping RPM and got to his base set point of 700 the timing was still at 21, which I thought surely should be enough to keep it running.
So I started thinking air flow. Thats when I noticed the desired idle rpm in the log at 625, obviously well below the base set point. So I'm thinking any and all stall savers are off the table aty this point

Then after the stall and restart, the desired rpm seemed to match the table.
BUT then at the end of the log it is back down to 625, just as it was at start up too

[dhoagland]

Curious where the 200 comes from for IAC effective area MAX?

[horsepowerguru427]

I saw that as well and compared to a few files. I had no idea where it came from so i just left it, IIRC. I wanna say the file i had, it was in the 80's, not the 200s

[Kzhurley]

Are you sure of the injector part number?
That 12631214 is a crank sprocket.

Sorry it?s 12613412. 50lb flex fuel injectors.

[Kzhurley]

Curious where the 200 comes from for IAC effective area MAX?

I see what you mean about that number not making sense. I copied some parts from another tune I had done for another vehicle and didn?t notice that being different than the 4 or 5 other downloaded tunes I?ve compared to for the throttle stuff. I?ve been copying parts from a dbc throttle tunes to makes sure I can get as much as I can right.
I will change that back to a lower value I?ve seen in other tunes.

[Kzhurley]

IMHO desired idle speed is too low. I'd go 800 since you are a manual. if it was an auto maybe it would do ok at 700.

I'd also encourage using a wideband to get the VE fully flushed out as the fuel trims move to slow to capture how rich or lean it might be in decel or idle dip areas. Use fuel trims as final say.. but the first several passes should be done with a wideband.

I was wondering about that. For some reason this cam doesn?t seem to lope very much at all. I wonder if it was a knockoff in an Elgin box? When I installed I just quickly checked ptv and put it together. I guess I will have to check into that also.

I haven?t tuned much of the ve yet due to the stalling coming to a stop. I could plug the wideband in and tune the idle areas though since it will idle all day good.

[Kzhurley]

I dont have data for those injectors, but all the necessary parameters were altered, so I'll go on the assumption that theyre correct for now. Not much underspeed spark to try and save it, I added some for you. Timing tables look bad around idle and all over. Huge valleys and dips its has to overcome if it hits those areas. I smoothed those out for you as well based on stock timing tables and what changes you had.

No guarantees, but heres an altered file....

Thanks for checking that out. I will plug it in and see if it helps.

[Kzhurley]

Would it be a good idea to swap os to something I can get dbc and manual trans on the 1mb p59 and start over with a fresh tune? Would being a 5.7l l31 vortec base tune with a 6.0l segment possibly leave unseen tables incorrrect?

[horsepowerguru427]

Sorry it?s 12613412. 50lb flex fuel injectors.

I double checked the injector data with what i have for 12613412 and you data was close enough. There were a few cells on the Vac vs volts that was off a very small percent but other than that it was spot on.

[Kzhurley]

Not sure if this might help, and I'd also like to know what determines Desired idle RPM (I will search later but dont have time right now.

While looking at his stall condition I noticed when he was dropping RPM and got to his base set point of 700 the timing was still at 21, which I thought surely should be enough to keep it running.
So I started thinking air flow. Thats when I noticed the desired idle rpm in the log at 625, obviously well below the base set point. So I'm thinking any and all stall savers are off the table aty this point

Then after the stall and restart, the desired rpm seemed to match the table.
BUT then at the end of the log it is back down to 625, just as it was at start up too

I am also unsure where that 625 is coming from. Could it possibly be leftover from the l31 5.7l vortec export tune i used for the base os?

[dhoagland]

I am also unsure where that 625 is coming from. Could it possibly be leftover from the l31 5.7l vortec export tune i used for the base os?

I guess it could be. But the big question, what table is driving it...
This is one I'm going to continue to try and figure out. I went back and looked at some stalls from an LQ4 I'm helping a guy with and the only changes in his were higher commanded after the restart that matched the "start up" added rpm and then watched it phase out.