LSA lean hot start???

[Eperformance]

Hey guys

Im having an issue with a lean hot start, The setup is LSA (e67 ecu) full exhaust, CAI, overdriven supercharger, 90lb DW injectors, and a small cam.

I have tuned setups like this before, with no issues. the only difference with this setup is that i am using 90lb dw injectors where usually i use 65lb.
Using the 90lb injectors means that i have had to scale the injectors (IFR half, double stoich).

When i do a hot start i find the AFR is lean for 3 - 4 minutes then settles and goes rich. if i turn the car off again it will go lean again.
Comparing injector tip temp and intake valve temp, both seem to be around the same temp when lean and rich.

Is there something i am missing? I dont usually use injectors this large so i am a noob with the Double stoich method.

I know i am probably missing something that is right in front of my face

Attached scan and tune.

Thanks in advanceleanhot.hplv3.hpt

[GHuggins]

On phone and can't see the tune, but did you half the ivt terms too?

[Eperformance]

No i did not, Will see if that helps.

Thanks

[Eperformance]

Pretty sure i sorted it, i noticed i had halved the injector flow rate after i had already copy and pasted it into the flow rate table.
So i was just halving the already maxed out flow rate

Also halved the IVT terms as suggested by Ghuggins.

Fuelings a lot more consistent now.

[GHuggins]

Usually you wind up with cold start issues being lean from the IVT terms being off - make sure you go .6ish on your instrument cluster settings too for fuel economy reporting...

[Eperformance]

Still had some issue with this today. lost my log tho

Have it running about 5 - 10% rich until lean issue sorted, run the car for 2-3 minutes and it runs noticeably rich. turn the car off for 10 seconds
then start up, car runs for about 1 - 2 minutes 10 - 15% lean then gradually settles back to wear it was.

Ill get another scan later today.

[GHuggins]

You need to look into the rich after flash injector tip temp thread Not uncommon to actually have to add fuel with certain setups to the hotter tip temps...

[Eperformance]

Injector tip temp is the same before and after restart and intake valve temp is within 2 - 3 degrees?

[GHuggins]

Then it's either injection timing causing fueling to change with heat soaking - yes it's possible - or a voltage setting or offset settings or something like that for the injectors...

[Eperformance]

Then it's either injection timing causing fueling to change with heat soaking - yes it's possible - or a voltage setting or offset settings or something like that for the injectors...

Will look into it thanks

[Area47]

What year is the v/zl1? You shouldn't have had to half anything to run 90's in it.

[GHuggins]

Yeah as long as you have values up to the 480 cell your good.

[Area47]

for an idea on reference, you may hit 75 psi on pressure on the low end hit and slowly drop to 65-70 through the run. Assuming it's light mods without any fpcm tinkering. right click, column, units, change it to psi to see where it falls at.

[Eperformance]

My values max out at about 85psi, I thought that would be the case, i data logged pressure delta and it seemed to be within the values.
Just thought it was good practice to not have any values maxed.

[OneTwo]

Usually you wind up with cold start issues being lean from the IVT terms being off - make sure you go .6ish on your instrument cluster settings too for fuel economy reporting...

Why 0.6ish? If IFR was put in at exactly half value, shouldn't the instrument cluster also be an exact multiple (either half or double, which ever is the right way for the reporting to be correct)?

[Area47]

Why 0.6ish? If IFR was put in at exactly half value, shouldn't the instrument cluster also be an exact multiple (either half or double, which ever is the right way for the reporting to be correct)?

there is error built into it and this keeps the error the same.

[ddtech]

Pull it out the maf area 2200-3500hz, see if that helps, i'd pull 10%, if not, add it, do not trust the fuel trims all the time. I've fought this before.

[Eperformance]

*update*
Scanned the the vehicle today finally, i have noticed that when the car is started and fuel trims are lean, control module voltage is 14.6 volts. Fuel trims only settle
when control module voltage drops down to 12.5 volts. I have attached a scan at 9.45 of the scan i turn off the vehicle, and restart after 8 seconds control module voltage
goes from 12.5 to 14.6 and fuel trims go lean. I would assume this would mean my injector offset vs IGN voltage table is incorrect???
This is the data that is suppled by the injector supplier though???LEAN HOT.hplfinal.hpt

[GHuggins]

Injector data isn't always 100% correct - change it and see if it doesn't get better - something else could possibly still be at play, but I would say this is most likely your cause

[Eperformance]

Spent a bit of time dialling in the offset vs pressure vs IGNV table, and it sorted my issue. Got my hot starts spot on