E67 2.4 LE5 Ecotec STAND ALONE HELP!

Hey guys! I am working on doing a stand alone E67 computer for my 2.4L ecotec motor in my sand car. The computer is out of a 2008 Cobalt SS. I currently am troubleshooting random misfires at idle. It seems to run out fine once you roll into the throttle, but it falls all over its face when you first roll into throttle. I have tried to delete all VATS and codes, but wondered if anyone had any ideas what should be deleted on this computer for a complete stand alone ecu? ANY help would be greatly appreciated! Thanks!

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Figured I would at least attach an image of what I am working on. It has a UMP air filter system on it with 3 inch tubing going to the throttle body. It has the MAF in it. I wondered if this could be something that could cause the random misfire? It used to be set up for speed density with MEFI-5 tuning.

I'm not up to date on anything 4 cylinder related but I know they will ask that you post the tune file and any logs you have.

It helps to see what you are seeing.

I think the LE5 is a NA motor, is the computer for a NA motor too? Just asking because it could be an issue if it's a supercharged computer running a NA motor.

What is the details on the motor setup?

I don't have the file at the moment, but yes, it is a N/A motor. All stock except it has a custom exhaust. I will take some pictures of the motor to see what I am working with.

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Here are the pictures of it. Sorry they are so dirty and dark. Let me know if you would like to see anything specific that may help diagnose. The wire harness is not in a loom yet because I am still trying to get it all solved first before making it look good.

remove the breather filter and run it properly with the line after the maf. returnless style fuel system? What is the OS on the ecm?

Are you talking about removing the blue filter? What is the correct way to run the line? It has an aeromotive fuel regulator, so yes, it does return fuel. I have it set at 58 psi. Not sure about the OS, it is stock Cobalt SS. Thanks!

Yes, the crankcase is supposed to get measured air from the intake air tubing after the MAF.
Also noticed that MAF is between two curved hoses sections.(usually mounted in a straight section) Have you done any adjustments to the MAF table?
Have you tried failing the MAF to see if the engine runs better in SD?
Ive been working on a boosted LE5\E67 myself, I have learned a ton from this Forum!

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Here is what I did for the measured air. I have not done anything with the MAF table to correct values. Hopefully will be able to mess with it early this week. Really want to get this solved, as I am wanting to do a turbo set up as well! Thank you for all of your help!

Looks like you have it hooked up to manifold vacuum??? ( fitting on manifold) there will be no fresh air pulled into the crankcase, and you may see a lot of oil in the intake manifold with this setup.