P1124 & P1126 Codes What to look for with Durametric?

[BFeller]

I have a 1998 Boxster 2.5 with @ 110,000 miles and had those codes show up. They came up the second trip in the car after I noticed a little surging at idle. I have cleared the codes. Then hooked up the Durametric. I see no pending codes - but the idle still surges. I can't hear any air leaks with the engine cover off. I haven't cleaned the MAF yet. The AOS is likely original. However there was no change in idle when removing the oil cap and strong suction can be heard. Placing my hand directly over the oil filler showed no change. I check the gas cap and that looks great - no cracking around the oring.

What should I be looking for using the Durametric as far as items to graph and view?

Thanks - Brett