'98 A4 2.8 not running correctly.

[mxhowes at aol.com]

I have a '98 2.5 A4 Avant 5-speed (215K miles) that runs flawlessly 98% of the time but....sometimes it will cut out for just a split second when accelerating gently or it feels like it is losing power monetarily but then runs fine. The other problem will generally happen when it's hot and you are stuck in traffic and it doesn't want to idle (acts just like a large vacuum leak)
I have changed the plugs, checked all over for vacuum leaks, checked the -N80-  EVAP canister purge valve (a while ago I was getting a P0455).  I have also cleaned the MAF.
Over the last month these are the codes that have been stored not very often does the CEL come on 

There is a handful of different codes here and the MAF could be the culprit but I don't have a spare 'known good working MAF' in my tool box and hate to spend the bucks on a new one. Mine is the Hitachi unit. I can hook up VCDS-lite and get some MAF readings but don't know what #'s I am looking for. I have also read about just disconnecting the MAF and after a short period of adjustment buy the computer see if the problem goes away. (it's hard to do because sometimes the car may run for 4 or 5 days without missing a beat)

Thanks for any help,
Jim

Saturday, 25 April 2015, 17:06:42.

VCDS-Lite Version: Release 1.2

Control Module Part Number: 4D0 907 551 AH
  Component and/or Version: 2.8L V6/5V  MOTR HS D02
           Software Coding: 06201
            Work Shop Code: WSC 26118
                      VCID: 6CAB47B30F93

3 Faults Found:
17537 -  Fuel Trim; Bank 2 (Mult): System too Rich
        P1129 - 35-10 -   - - Intermittent
17535 - Shareware Version. To Decode all DTCs
        P1127 - 35-10 - Please Register/Activate - Intermittent (long term fuel trim mult, Bank 1 system too rich)
16487 - Shareware Version. To Decode all DTCs
        P0103 - 35-10 - Please Register/Activate - Intermittent (Mass or volume air Flow circut High Input)
---------------------------------------------------------------------------
Monday, 27 April 2015, 09:22:49:43507

VCDS-Lite Version: Release 1.2
Control Module Part Number: 4D0 907 551 AH
  Component and/or Version: 2.8L V6/5V  MOTR HS D02
           Software Coding: 06201
            Work Shop Code: WSC 26118
                      VCID: 6CABEE400F93

4 Faults Found:
17537 -  Fuel Trim; Bank 2 (Mult): System too Rich
        P1129 - 35-10 -   - - Intermittent
17535 -  Fuel Trim; Bank 1 (Mult): System too Rich
        P1127 - 35-10 -   - - Intermittent
16487 -  Mass Air Flow Sensor (G70): Signal too High
        P0103 - 35-10 -   - - Intermittent
16795 -  Secondary Air Injection System: Incorrect Flow Detected
        P0411 - 35-10 -   - - Intermittent
---------------------------------------------------------------------------
Thursday, 14 May 2015, 16:51:45:43507

VCDS-Lite Version: Release 1.2
Control Module Part Number: 4D0 907 551 AH
  Component and/or Version: 2.8L V6/5V  MOTR HS D02
           Software Coding: 06201
            Work Shop Code: WSC 26118
                      VCID: 6CABEE400F93

4 Faults Found:
16486 -  Mass Air Flow Sensor (G70): Signal too Low
        P0102 - 35-10 -   - - Intermittent
17537 -  Fuel Trim; Bank 2 (Mult): System too Rich
        P1129 - 35-10 -   - - Intermittent
17535 -  Fuel Trim; Bank 1 (Mult): System too Rich
        P1127 - 35-10 -   - - Intermittent
17549 -  Load Calculation Cross Check: Implausible Value
        P1141 - 35-10 -   - - Intermittent
---------------------------------------------------------------------------
Friday, 15 May 2015, 09:40:13:43507

VCDS-Lite Version: Release 1.2
Control Module Part Number: 4D0 907 551 AH
  Component and/or Version: 2.8L V6/5V  MOTR HS D02
           Software Coding: 06201
            Work Shop Code: WSC 26118
                      VCID: 6CABEE400F93

1 Fault Found:

16795 -  Secondary Air Injection System: Incorrect Flow Detected
        P0411 - 35-00 -   -
---------------------------------------------------------------------------
Saturday, 23 May 2015, 10:45:59:43507

VCDS-Lite Version: Release 1.2
Control Module Part Number: 4D0 907 551 AH
  Component and/or Version: 2.8L V6/5V  MOTR HS D02
           Software Coding: 06201
            Work Shop Code: WSC 26118
                      VCID: 6CABEE400F93

1 Fault Found:

16486 -  Mass Air Flow Sensor (G70): Signal too Low
        P0102 - 35-10 -   - - Intermittent

---------------------------------------------------------------------------