Sorento Misfire - no codes

It's an 2005 LX 4X4. Plugs and wire replaced approx 12,000 kms ago. All was well until about 3 weeks ago. It misfires but no codes show when scanned. Misfire is most evident when under load.

While driving to and from work, I ran a recorder (CRRecorders) which scans (and saves) at 2 second intervals looking for a drop in rpm etc. - Anything glaring which may indicate where the problem exists. Nada

Any assistance is greatly appreciated.

Cheers
Here are some scan stats:
@idle
ST fuel trim B1 & B2 - 0.0
LT fuel trim B1 - 15.5, B2 13.3

IGN timing 10 - 12
MAF 3.69 g/s @ 800 rpm, 1.3v
ISC @47 Load@14 TPS@.76

There are two reading that I am not familiar with, I am assuming that they are KIA specific? ISC Real Time Adapt - 1, ISC Long Time Adapt - (-24)