Lean After Reflash OLSD

[Galgo]

Hello All,

I've got a 4.8 on the 0411 ecm. I have the 3 bar os running in OL. I just had it out and was doing some VE tuning. I logged the WB error % and multiplied the VE table by %-half. It was running about 20-25% rich before changing the VE. I also changed the Power Enrichment and a little bit of Idle Air Flow at the same time. When I started the car, it started running about 25% lean. I started working backwards and changed the VE back and then the PE, and then the Idle Air. Flashing between each change to try and figure out which one made such a drastic change to my Lambda. After changing all of them back, it was still running 25% lean. Is there something that causes the car to run lean for a while after a reflash? Is it bad injector data? I have been chipping away at the tune on this car for a while. I've seen this problem once or twice before but always wondered why it happens. It doesn't seem to be consistent.

Engine spec's: 4.8, LJSM turbo cam, Siemens Deka 80lb injectors. I got injector data off LS1tech that looked like a spreadsheet that was put out by Dave Steck.

I've posted my tune.

Edit: The tune is also Scaled. I started with a base tune from Matt Happel

Thanks!!

Starting Over.hpt

[cobaltssoverbooster]

sounds like bad injector data.
typically incorrect values here make the copy paste results work in very mysterious ways due to a percent change of the ecu table not matching the physical percent change on the injector flow.

[Freshnfrooty]

I have been fighting a similar problem with my car, running OLSD but goes way lean on hot startups and then levels back off to what im commanding in the VE after 5-10 minutes. It feels like there is a table that we are missing, or just bad injector data i guess? Either way i'm curious to see if you find a solution because I have not been able to so far. Best of luck

[anniversaryss]

Is the IAT much higher after the restart?

People have lots of trouble with cylinder charge and the bias settings is OLSD.

[Galgo]

sounds like bad injector data.
typically incorrect values here make the copy paste results work in very mysterious ways due to a percent change of the ecu table not matching the physical percent change on the injector flow.

Thats what I was kind of thinking also, but I dont think it could be the case since I put the old ve data back in and it still ran lean. If it was bad injector data it should have gone back to being way rich when I put the old ve back in

[Galgo]

I have been fighting a similar problem with my car, running OLSD but goes way lean on hot startups and then levels back off to what im commanding in the VE after 5-10 minutes. It feels like there is a table that we are missing, or just bad injector data i guess? Either way i'm curious to see if you find a solution because I have not been able to so far. Best of luck

I had a similar problem before where the iat was causing that problem. It was due to a couple of things. First, the iat sensor was getting heat soaked and then reading incorrectly. Second, the iat bias was incorrect. I think I removed the iat bias all together so that it didn?t effect the iat calculations. Third, and the largest, was my iac was maxxed out. I opened the throttle more and reset my tps sensor. This seemed like it would work opposite than desired, but seemed to fix my issue. You?ll know if this is your problem by letting it idle and watching the iat climb and the afr going lean proportional to the iat getting hotter.

[Galgo]

Is the IAT much higher after the restart?

People have lots of trouble with cylinder charge and the bias settings is OLSD.

No sir. I?ve experienced that before and was able to get it corrected. Unfortunately this is different.

[Galgo]

Bump