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AEM Infinity Large discrepancies in VE from day to day

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Hey Guys, I am having a strange issue. I am in the process of getting a car ready for tuning on the Dyno. I got the fueling dialed in for most of the part throttle/cruising areas and at idle. The issue I am having is today I started the car and and let it get all the way back up to operating temperature and I noticed the Injector feedback was at around -20% or -0.20 at idle so I cruised around and sure enough the VE table was between 15% and 20% to rich. I noticed a similar issue when I got the car running for the first time after the infinity install. I had it idling right on target then the next day I started it the VE was off by a large margin again. Is this something any of you have run into in the past? I will be sure to get logs of both instances to see if maybe the battery voltage is changing and the injector dead times are wrong or something. I am using AEM's calibration for the injector that are fitted to the engine.

Any ideas or help is much appreciated! Thank you everyone.

It's not unusual to see some discrepancy from day to day but 20% is a little excessive. Understand that the VE model is still calculating the mass airflow rather than directly measuring it with a MAF. This means that you can expect some day to day variations but these should be within +/-3-5% max. In the situation you're dealing with I'd suggest logging all the key inputs to the fuel model and see what is different. It may be that your IAT is dramatically different between the two tests.

Thanks Andre, ya I am used to seeing small discrepancies but never such large ones. I am going to go through all the logs that I have and do some more logging when the error is presenting itself and see what might be causing it. I'll post what I come up with on here. Thanks guys!

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