2001 Jetta Wolfsburg 1.8t code P0170

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Hi everybody,

First timer, here. I know everything I know about my car through this site so thanks!

I've got a 2001 Jetta Wolfsburg 1.8T with just under 104K miles. It's running fine but I've been chasing down this P0170 code for a few months and now my inspection's due so the pressure's on to get it fixed (as if it wasn't before).

The car runs fine with the exception of cold starts. I've scoured the forums and hope I haven't missed anything obvious, but here's what I've done so far:
-replaced MAF (just tested this under load at redline and got readings of ~156 g/s. My car has an APR chip so I assume these readings are good. I aslo assume this rules out the MAF as the culprit.
-checked for obvious vacuum leaks to no avail
-replaced pre-cat O2 sensor (was originally throwing P0133 so it wasn't just on a whim)

I'm still inclined to suspect a vacuum leak and need to do replace the braided lines anyway but it must be a small one. So my questions:
1. Would VAG-COM give me more info than my OBDII scanner about fuel trim specifically and narrow down the possible issues (ie, determine whether it's a vacuum leak or a sensor failure)?
2. Since I reset my CEL, all monitors have come back up except the catalytic converter monitor. That one still comes back incomplete. Is it possible the post-cat O2 sensor is involved with that? I know it's not directly involved with fuel trim issues like the pre-cat sensor.
3. Do any VAG-COM owners in Austin (78704) feel like helping out?

cheers

[integrin]

Just to be clear, I replaced the MAF, reset the CEL, and then just tested the new MAF as a sanity check today when the P0170 code came back.

[integrin]

And finally, here's the data from my scanner, just in case someone spots something I didn't. I'll be quiet now.

O2 Monitor Test
O2 Bank1 Sensor1
$81 (Values)
MOD : $10
MEAS: 118
MIN : 90
MAX : 255
$82 (Values)
MOD : $10
MEAS: 128
MIN : 90
MAX : 255
$83 (Values)
MOD : $10
MEAS: 99
MIN : 15
MAX : 205
$84 (Values)
MOD : $10
MEAS: 51
MIN : 0
MAX : 255
O2 Bank1 Sensor2
$81 (Values)
MOD : $10
MEAS: 118
MIN : 90
MAX : 255
$82 (Values)
MOD : $10
MEAS: 128
MIN : 90
MAX : 255
$83 (Values)
MOD : $10
MEAS: 99
MIN : 15
MAX : 205
$84 (Values)
MOD : $10
MEAS: 51
MIN : 0
MAX : 255

Live Data
DTC_CNT 1
FUELSYS1 CL
FUELSYS2 N/A
LOAD_PCT(%) 3.5
ETC(°C) 94
SHRTFT1(%) 0.0
LONGFT1(%) 3.1
RPM(/min) 3970
VSS(km/h) 58
SPARKADV(°) 2
IAT(°C) 36
MAF(g/s) 9.25
TP(%) 7.8
AIR_STAT OFF
O2S B1S12--B2S----
O2B1S2(V) 0.005
OBD OBD&OBD2
EQ_RAT11 1.999
O2S11(mA) 2.395
------------------
DTC_CNT 1
FUELSYS1 OL_Fault
FUELSYS2 N/A
LOAD_PCT(%) 43.9
ETC(°C) 93
SHRTFT1(%) 0.0
LONGFT1(%) 3.1
RPM(/min) 3595
VSS(km/h) 53
SPARKADV(°) 38
IAT(°C) 33
MAF(g/s) 15.75
TP(%) 11.0
AIR_STAT OFF
O2S B1S12--B2S----
O2B1S2(V) 0.735
OBD OBD&OBD2
EQ_RAT11 0.780
O2S11(mA) -0.145
------------------
DTC_CNT 1
FUELSYS1 CL
FUELSYS2 N/A
LOAD_PCT(%) 4.7
ETC(°C) 93
SHRTFT1(%) 0.0
LONGFT1(%) 3.1
RPM(/min) 1343
VSS(km/h) 45
SPARKADV(°) 5
IAT(°C) 35
MAF(g/s) 2.25
TP(%) 2.0
AIR_STAT OFF
O2S B1S12--B2S----
O2B1S2(V) 0.585
OBD OBD&OBD2
EQ_RAT11 0.750
O2S11(mA) -0.988
------------------
DTC_CNT 1
FUELSYS1 CL
FUELSYS2 N/A
LOAD_PCT(%) 1.6
ETC(°C) 93
SHRTFT1(%) 2.3
LONGFT1(%) 3.1
RPM(/min) 759
VSS(km/h) 27
SPARKADV(°) 13
IAT(°C) 38
MAF(g/s) 2.25
TP(%) 2.4
AIR_STAT OFF
O2S B1S12--B2S----
O2B1S2(V) 0.625
OBD OBD&OBD2
EQ_RAT11 0.958
O2S11(mA) -0.129
------------------
DTC_CNT 1
FUELSYS1 CL
FUELSYS2 N/A
LOAD_PCT(%) 2.0
ETC(°C) 93
SHRTFT1(%) 0.0
LONGFT1(%) 3.1
RPM(/min) 1946
VSS(km/h) 11
SPARKADV(°) 26
IAT(°C) 36
MAF(g/s) 16.25
TP(%) 6.3
AIR_STAT OFF
O2S B1S12--B2S----
O2B1S2(V) 0.665
OBD OBD&OBD2
EQ_RAT11 0.787
O2S11(mA) -0.734
------------------
DTC_CNT 1
FUELSYS1 CL
FUELSYS2 N/A
LOAD_PCT(%) 2.4
ETC(°C) 93
SHRTFT1(%) -17.2
LONGFT1(%) 3.1
RPM(/min) 781
VSS(km/h) 5
SPARKADV(°) 5
IAT(°C) 38
MAF(g/s) 7.25
TP(%) 4.3
AIR_STAT OFF
O2S B1S12--B2S----
O2B1S2(V) 0.715
OBD OBD&OBD2
EQ_RAT11 0.969
O2S11(mA) -0.344
------------------
DTC_CNT 1
FUELSYS1 CL
FUELSYS2 N/A
LOAD_PCT(%) 36.5
ETC(°C) 93
SHRTFT1(%) 13.3
LONGFT1(%) 3.1
RPM(/min) 3542
VSS(km/h) 28
SPARKADV(°) 25
IAT(°C) 34
MAF(g/s) 46.25
TP(%) 36.9
AIR_STAT OFF
O2S B1S12--B2S----
O2B1S2(V) 0.030
OBD OBD&OBD2
EQ_RAT11 0.957
O2S11(mA) -0.266
------------------
DTC_CNT 1
FUELSYS1 CL
FUELSYS2 N/A
LOAD_PCT(%) 20.0
ETC(°C) 94
SHRTFT1(%) 14.1
LONGFT1(%) 3.1
RPM(/min) 3629
VSS(km/h) 53
SPARKADV(°) 2
IAT(°C) 34
MAF(g/s) 52.75
TP(%) 21.6
AIR_STAT OFF
O2S B1S12--B2S----
O2B1S2(V) 0.690
OBD OBD&OBD2
EQ_RAT11 0.940
O2S11(mA) -0.258
------------------
DTC_CNT 1
FUELSYS1 OL_Fault
FUELSYS2 N/A
LOAD_PCT(%) 74.5
ETC(°C) 95
SHRTFT1(%) 0.0
LONGFT1(%) 3.1
RPM(/min) 5712
VSS(km/h) 85
SPARKADV(°) 35
IAT(°C) 34
MAF(g/s) 12.75
TP(%) 8.2
AIR_STAT OFF
O2S B1S12--B2S----
O2B1S2(V) 0.635
OBD OBD&OBD2
EQ_RAT11 1.999
O2S11(mA) 2.320
------------------
DTC_CNT 1
FUELSYS1 OL-Drive
FUELSYS2 N/A
LOAD_PCT(%) 8.6
ETC(°C) 95
SHRTFT1(%) 0.0
LONGFT1(%) 3.1
RPM(/min) 4747
VSS(km/h) 71
SPARKADV(°) 17
IAT(°C) 34
MAF(g/s) 90.75
TP(%) 15.3
AIR_STAT OFF
O2S B1S12--B2S----
O2B1S2(V) 0.730
OBD OBD&OBD2
EQ_RAT11 0.841
O2S11(mA) -0.492
------------------
DTC_CNT 1
FUELSYS1 OL-Drive
FUELSYS2 N/A
LOAD_PCT(%) 2.7
ETC(°C) 94
SHRTFT1(%) 0.0
LONGFT1(%) 3.1
RPM(/min) 1043
VSS(km/h) 58
SPARKADV(°) 10
IAT(°C) 36
MAF(g/s) 2.00
TP(%) 2.4
AIR_STAT OFF
O2S B1S12--B2S----
O2B1S2(V) 0.450
OBD OBD&OBD2
EQ_RAT11 0.958
O2S11(mA) -0.637
------------------
DTC_CNT 1
FUELSYS1 OL_Fault
FUELSYS2 N/A
LOAD_PCT(%) 20.0
ETC(°C) 93
SHRTFT1(%) 0.0
LONGFT1(%) 3.1
RPM(/min) 2838
VSS(km/h) 63
SPARKADV(°) 23
IAT(°C) 34
MAF(g/s) 5.00
TP(%) 4.7
AIR_STAT OFF
O2S B1S12--B2S----
O2B1S2(V) 0.710
OBD OBD&OBD2
EQ_RAT11 0.810
O2S11(mA) -1.023
------------------
DTC_CNT 1
FUELSYS1 OL_Fault
FUELSYS2 N/A
LOAD_PCT(%) 5.5
ETC(°C) 93
SHRTFT1(%) 0.0
LONGFT1(%) 3.1
RPM(/min) 2887
VSS(km/h) 65
SPARKADV(°) 6
IAT(°C) 33
MAF(g/s) 5.25
TP(%) 5.1
AIR_STAT OFF
O2S B1S12--B2S----
O2B1S2(V) 0.595
OBD OBD&OBD2
EQ_RAT11 0.945
O2S11(mA) -0.242
------------------
DTC_CNT 1
FUELSYS1 OL_Fault
FUELSYS2 N/A
LOAD_PCT(%) 5.5
ETC(°C) 92
SHRTFT1(%) 0.0
LONGFT1(%) 3.1
RPM(/min) 3196
VSS(km/h) 71
SPARKADV(°) 36
IAT(°C) 33
MAF(g/s) 15.50
TP(%) 11.0
AIR_STAT OFF
O2S B1S12--B2S----
O2B1S2(V) 0.710
OBD OBD&OBD2
EQ_RAT11 0.780
O2S11(mA) -1.102
------------------
DTC_CNT 1
FUELSYS1 OL-Drive
FUELSYS2 N/A
LOAD_PCT(%) 5.9
ETC(°C) 91
SHRTFT1(%) 0.0
LONGFT1(%) 3.1
RPM(/min) 3017
VSS(km/h) 67
SPARKADV(°) 13
IAT(°C) 33
MAF(g/s) 35.50
TP(%) 16.9
AIR_STAT OFF
O2S B1S12--B2S----
O2B1S2(V) 0.665
OBD OBD&OBD2
EQ_RAT11 0.942
O2S11(mA) -0.391
------------------

[integrin]

It was indeed the post-cat o2 sensor in my case. Replacing that did the trick.