[san rensho]

I am getting persistent 1128 and 1130 codes. The duramteric shows fuel trims (FRA, RCAT) at the max, 4.5+. Also, the MAF flow is as 9-10 kg/min, where before, it was around 13.5 (spec is 15 +/- 1.5). I've installed three different MAFs and they are all around 10, so I'm ruling out the MAF as the culprit.

I think its pretty clear I have a vacuum leak. I've sprayed carb cleaner on most of the vacuum lines and connections behind the MAF, but I haven't been able to detect a vacuum leak.

Is it possible that a failed AOS will cause a vacuum leak and 1128 and 1130 codes? If so, can I test the AOS by disconnecting the AOS connector at the throttle body and plug everything up, then if the MAF flow readings go back to normal, the AOS is the cause of the vacuum leak?

Another code I am getting is a failed evap valve. Will a bad evap valve cause a vacuum leak?

This is driving me crazy.