[rtl32]

You're dealing with two different problems.

In your sport+ log the biggest pull shows a 5-600psi fuel pressure dip which is when you would've experienced a backfire/fart/power cut. Very normal on these cars, very common issue, the fuel pump won't keep up with a tune. Just put a HPFP on and it'll go away. My OEM HPFP wouldn't even keep up with my car on a stage 1 tune. It even did this on the stock tune a couple times as well.

Now for the idle problems 98% of them are caused by bad/mis gapped plugs or bad coils, and the other 2% are caused by messy and partially stuck injectors. I did my injectors at 50k and my plugs every 10k and my coils every 15k and it keeps everything fresh. If its not one of those things you have an air leak but that would throw codes.

Upgrade your HPFP or go back to stage 1, and make sure your plug gap is okay, your coils are good, and if you're still having problems maybe do injectors but check back for that because you would be having other problems if thats the issue as well (namely low load throttle transitions will get stumbly, cold starts might be rough for the first 2-5 seconds, and you'll have some timing corrections isolated to cylinders after you've already confirmed coil/plug are good if injectors are the case).