refit the s3 injectors and up the rail pressure, idle will come back. rs4 injectors are the incorrect spray pattern and cause idle issues
that's the caveat in my statement, "IF". and by pressure i meant fpr/filter
Sorry.....Didn't see any if in your statement,which is why I posted those comments up.
Also....very sorry to see what happened to your car,and wish you the best for getting it running again shortly.
My reading of the spec we can see on this car is that it's been reasonably well modded,with a turbo that should go to the mid 400's assuming everything else is properly set up etc.
As a part of fitting RS4 injectors,you would need the RS4 regulator,or the requested and delivered rail pressures would be unlikely to match,and the flow rates through the different injectors would also be incorrect if the mapping wasn't RS4 injector specific.
From looking at CC's website and pages,their Stg3 equates roughly to Revo's,which is a hybrid/BT kit spec.
The spray pattern problem with the RS4 injectors doesn't produce idle issues,but can produce some smoking under full load,and as I said was something that one tuner in particular used to make a big deal of,until they found that no-one was really interested in that aspect.
This is ATP's kit....
400HP - GT2871R Stock Location Turbo & Manifold for 2.0T FSI / TSI Models : atpturbo.com
Stock placement,and uses a GT2871 plus one of ATP's cast manifolds.
APR's kit uses the GTX2867 which will flow a bit more than the GT2871 so I think it's likely to be the ATP on reflection,but makes little difference in terms of the injectors,as most aside from APR use RS4 injectors for a hybrid or BT build.
On a humourous note,it always makes me smile when I see Tar-ox doing with 10 or 12 pots,what AP can do with 6.