Vehicle stalling/surging issue.

I am having an issue with my vehicle wanting to stall when coming to a stop or when letting off the throttle at a low speed. The rpms want to drop real low and then they will pick back up(to much) and then drop down even lower. It wants to repeat this until it eventually drops to low and then it stalls, although it doesn't do this all the time. On my +1 long hour trip home today it did this 5-10 times I believe. When coming to a stop (coast down I guess you would consider it) if I notice the rpms start swinging from 500-1000rpm I have to throw it in neutral and try and hold at 2000rpm and slowly bring the rpms down to try and keeps it from stalling all while trying to not run into the back of somebody. The tune file attached is set up for VE tuning so the MAF is failed but it will still do it with the MAF enabled. If you could point me into the direction of which tables to adjust that would be greatly appreciated. Thanks! Vehicle is a 2011 GMC 5.3, 6l80e 2800 yank, 224/228@114 Cam, CNC heads, stock intake, Ls3 tb, log manifold turbo kit.Attachment 64760

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Originally Posted by TAPyvehc93

I am having an issue with my vehicle wanting to stall when coming to a stop or when letting off the throttle at a low speed. The rpms want to drop real low and then they will pick back up(to much) and then drop down even lower. It wants to repeat this until it eventually drops to low and then it stalls, although it doesn't do this all the time. On my +1 long hour trip home today it did this 5-10 times I believe. When coming to a stop (coast down I guess you would consider it) if I notice the rpms start swinging from 500-1000rpm I have to throw it in neutral and try and hold at 2000rpm and slowly bring the rpms down to try and keeps it from stalling all while trying to not run into the back of somebody. The tune file attached is set up for VE tuning so the MAF is failed but it will still do it with the MAF enabled. If you could point me into the direction of which tables to adjust that would be greatly appreciated. Thanks! Vehicle is a 2011 GMC 5.3, 6l80e 2800 yank, 224/228@114 Cam, CNC heads, stock intake, Ls3 tb, log manifold turbo kit.Attachment 64760

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I had similar issues with my truck. Here are two tables:

Attachment 64762 Attachment 64763

I would adjust the idle speed minimum to match the Engine > Idle > RPM> Base Idle RPM > Target Idle Speed. Also... the Airflow Final Minimum values probably need to be adjusted. These numbers act like a idle speed adjustment screw on an old carburetor. Lower values mean lower idle speeds, higher numbers mean higher idle speeds. Go way too low, it'll stall. If you go too high, it'll race. Since you complain of stalling, I think you need to raise the Airflow Final Minimum values up to the column containing your targeted idle speed of 800 rpm. Once you get it in the ballpark, changes of 1% are noticeable. You can log desired idle speed against actual idle speed to see where it ends up. When you're done adjusting, the actual idle speed line will cross the desired idle speed line during run time. This was a good learning experience for me...

Oh okay. Ill give that a try and get back to you. I bet that will fix the issue since mine is set so low compared to the base idle. Thanks!

Raising the minimum airflow fixed it a bunch.Thanks