Random misfires

B7RS4, 103,000 miles.

current state: Misfires on 5,8,4,3, random/multiple misfire code P0768.

history:
my car has been running great for a long time. I bought it about 3 years ago. no issues. Good maintenance history. I went to piggie pipes about 12 months ago. It has continually been throwing codes for O2 sensors. Replaced a few, added spacers, still throwing codes. So, its coming time for me to get the thing an Echeck. I couldn’t get the O2 codes to go away, so I figured I’d just buy a set of used standard downpipes and toss them on and swap back after the car gets the OK. right before tossing on the downpipes on cold mornings I would notice the slightest hesitation when driving my daughter to school. didn’t notice it any other time. Only lasted for about 5 minutes and it would go away. no codes thrown. Figured it was just time for a carbon clean.

So, I had my local indy (~1 mile from my house) VW/Audi shop toss on the downpipes and after picking it up, it started having major random misfires. Almost undriveable. really bad. So, I opened her up for maintenance. I did plugs, coils, carbon clean, injector service - clean/seals (replaced one injector that the plastic was busted on), oil, filters (fuel, oil,cabin) - all the good stuff.

http://www.voidopolis.com/images/carbon-01.jpg

http://www.voidopolis.com/images/cleaned.jpg

After getting everything put back together, I’m still seeing the misfire problems. not anywhere near as bad as it was before, but still there. If I reset the codes, it runs somewhat normally and then goes back into a misfire condition. it seems to cycle through running rough and running semi-OK.

I’ve done some logging. I was reading in another thread about logging 003/103/106 to check the fuel system. I’ve included the details below from a scan and some data.

My assumption is that the downpipes that I bought are bad or plugged or something. my next step is to swap them back on to see if that changes anything. but I thought Id check with you guys to see if there is something else I should be looking at.

Monday,12,June,2017,19:04:14:39744
VCDS Version: 17.1.3.0 (x64)

VIN: License Plate: RS4-1

Mode 07: Pending emission related fault codes

Address 7E8: No fault code found.

Address 7EA: 5 Faults Found:
P0300 - Random/Multiple Cylinder Misfire Detected
P0305 - Cylinder 5: Misfire Detected
P0308 - Cylinder 8: Misfire Detected
P0304 - Cylinder 4: Misfire Detected
P0303 - Cylinder 3: Misfire Detected



Chassis Type: 8E (8E - Audi A4/S4/RS4 B6/B7 (2001 > 2008))
Scan: 01 02 03 08 09 0F 11 15 16 17 18 25 36 37 45 46 55 56 57 65
67 69 75 76 77

VIN: WUARU78E87N905669 Mileage: 167160km-103868miles

Address 01: Engine Labels: 079-910-560-BNS1.lbl
Part No SW: 8E1 910 560 A HW: 8E1 907 560
Component: 4.2L V8/4V FSI ª0060
Revision: 57H15— Serial number: XXXXXXXXXXXXXX
Coding: 01040009180F0160
Shop #: WSC 08252 444 57643
VCID: 244037D2E740BF61AD-8070

1 Fault Found:
006435 - Please Check DTC Memory of ECU Number 2
P1923 - 008 -
Freeze Frame:
Fault Status: 01101000
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 167159 km
Time Indication: 0

         Freeze Frame:
                RPM: 3800 /min
                Load: 17.6 %
                Speed: 74.0 km/h
                Temperature: 97.0°C
                Temperature: 44.0°C
                Absolute Pres.: 980.0 mbar
                Voltage: 13.589 V

Readiness: 0110 1101


Address 03: ABS Brakes Labels: 8E0-910-517.clb
Part No SW: 8E0 910 517 G HW: 8E0 614 517 BD
Component: ESP8 quattro H06 0150
Revision: 00000000 Serial number: 00000000000000
Coding: 0004533
Shop #: WSC 06335 000 00000
VCID: 2B52DCEE8A9E70196C-807E

1 Fault Found:
01826 - Sensor for Steering Angle (G85); Supply Voltage Terminal 30
000 - - - Intermittent
Freeze Frame:
Fault Status: 00100000
Fault Priority: 3
Fault Frequency: 15
Reset counter: 40
Time Indication: 0

         Freeze Frame:
                Hex Value: 0x0000
                Hex Value: 0x4222
                Hex Value: 0x0024
                Hex Value: 0x0197
                Hex Value: 0x0001

Address 08: Auto HVAC Labels: 8E0-820-043.lbl
Part No: 8E0 820 043 BM
Component: A4 Klimaautomat 3233
Coding: 00000
Shop #: WSC 00000
VCID: 6DD612F6270ABE2932-50E6

1 Fault Found:
01206 - Signal for Duration of Ignition Off Time
27-00 - Implausible Signal


Address 09: Cent. Elect. Labels: 8E0-907-279-8EC.lbl
Part No: 8E0 907 279 N
Component: int. Lastmodul ECE 0907
Coding: 01031
Shop #: WSC 65536
VCID: 3D76E2B637EAEEA9C2-4A3A

No fault code found.


Address 11: Engine II Labels: 079-910-560-BNS2.lbl
Part No SW: 8E1 910 560 A HW: 8E1 907 560
Component: 4.2L V8/4V FSI ª0060
Revision: 57H15— Serial number: XXXXXXXXXXXXXX
Coding: 01040009180F0160
Shop #: WSC 08252 444 57643
VCID: 244037D2E740BF61AD-8070

5 Faults Found:
000768 - Random/Multiple Cylinder Misfire Detected
P0300 - 001 -
Freeze Frame:
Fault Status: 01100001
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 167159 km
Time Indication: 0

         Freeze Frame:
                RPM: 3737 /min
                Load: 63.1 %
                Speed: 73.0 km/h
                Temperature: 97.0°C
                Temperature: 44.0°C
                Absolute Pres.: 980.0 mbar
                Voltage: 13.462 V

000773 - Cylinder 5
P0305 - 001 - Misfire Detected
Freeze Frame:
Fault Status: 01100001
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 167159 km
Time Indication: 0

000776 - Cylinder 8
P0308 - 001 - Misfire Detected
Freeze Frame:
Fault Status: 01100001
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 167159 km
Time Indication: 0

         Freeze Frame:
                RPM: 3737 /min
                Load: 63.1 %
                Speed: 73.0 km/h
                Temperature: 97.0°C
                Temperature: 44.0°C
                Absolute Pres.: 980.0 mbar
                Voltage: 13.462 V

000772 - Cylinder 4
P0304 - 001 - Misfire Detected
Freeze Frame:
Fault Status: 01100001
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 167159 km
Time Indication: 0

000771 - Cylinder 3
P0303 - 001 - Misfire Detected
Freeze Frame:
Fault Status: 01100001
Fault Priority: 0
Fault Frequency: 1
Reset counter: 255
Mileage: 167161 km
Time Indication: 0

         Freeze Frame:
                RPM: 746 /min
                Load: 44.7 %
                Speed: 3.0 km/h
                Temperature: 96.0°C
                Temperature: 45.0°C
                Absolute Pres.: 990.0 mbar
                Voltage: 13.335 V

Address 15: Airbags Labels: 8E0-959-655-94.lbl
Part No SW: 8E0 959 655 H HW: 8E0 959 655 H
Component: Airbag 9.41 H12 3840
Revision: 91H12384 Serial number: 0036N0G0R0F4
Coding: 0432607
Shop #: WSC 06335 000 00000
VCID: 3C70EFB27FF0E7A1F5-8068

Subsystem 1 - Part No: 8E0 910 339 B
Component: BF-Gewichtsens. 002 0070

Subsystem 2 - Serial number: 3HLKX

Subsystem 3 - Serial number: 0001.01.000000200000000000ÿ†63

Subsystem 4 - Serial number: 000000ÿ†6332DRB4047A4DA8$ÿ†63

Subsystem 5 - Serial number: A4DA8$ÿ†6342DRB4047B0E2E-ÿ†63

Subsystem 6 - Serial number: B0E2E-ÿ†6352ARB401EC90A4Wÿ†63

Subsystem 7 - Serial number: C90A4Wÿ†6362ARB401E90B6AYÿ†63

Subsystem 8 - Serial number: 90B6AYÿ†63729RB401EF80D5$ÿ†63

Subsystem 9 - Serial number: F80D5$ÿ†63829RB401EF80A2Yÿ

Subsystem 10 - Serial number: F80A2Yÿ

No fault code found.


Address 16: Steering wheel Labels: 8E0-953-549-T.lbl
Part No: 8E0 953 549 T
Component: Lenksáulenmodul 0301
Coding: 04441
Shop #: WSC 06335
VCID: 4480975254009F618D-4A3A

2 Faults Found:
01301 - Control Module for Voice Recognition (J507)
49-00 - No Communications
01303 - Telephone Transceiver (R36)
49-00 - No Communications


Address 17: Instruments Labels: 8E0-920-9xx-8EC.lbl
Part No SW: 8E0 920 982 R HW: 8E0 920 982 R
Component: KOMBI+WFS 4 H14 0100
Revision: 0100 Serial number: 00000000000000
Coding: 0023268
Shop #: WSC 03131 444 12345
VCID: 3D76E2B667EAEEA9C2-5072

1 Fault Found:
01303 - Telephone Transceiver (R36)
004 - No Signal/Communication


Address 25: Immobilizer Labels: 8E0-920-9xx-8EC.lbl
Part No SW: 8E0 920 982 R HW: 8E0 920 982 R
Component: KOMBI+WFS 4 H14 0100
Revision: 0100 Serial number: 00000000000000
Coding: 0023268
Shop #: WSC 03131 444 12345
VCID: 3D76E2B667EAEEA9C2-5072

1 Fault Found:
01303 - Telephone Transceiver (R36)
004 - No Signal/Communication


Address 46: Central Conv. Labels: 8E0-959-433-MAX.clb
Part No: 8E0 959 433 CG
Component: Komfortgerát T7B 4135
Coding: 11820
Shop #: WSC 06335
VCID: 78F833A258480B81D1-4A3A

Subsystem 1 - Part No: 8E1959801G
Component: Tõrsteuer.FS BRM 0706

Subsystem 2 - Part No: 8E1959802G
Component: Tõrsteuer.BF BRM 0706

Subsystem 3 - Part No: 8E0959801E
Component: Tõrsteuer.HL BRM 0606

Subsystem 4 - Part No: 8E0959802E
Component: Tõrsteuer.HR BRM 0606

2 Faults Found:
00955 - Key 1
35-10 - - - Intermittent
00956 - Key 2
35-10 - - - Intermittent


Address 55: Headlight Range Labels: 4F0-910-357.lbl
Part No SW: 4F0 910 357 F HW: 4F0 907 357 F
Component: AFS 1 H01 0020
Revision: 00000001 Serial number:
Coding: 0000019
Shop #: WSC 06335 000 00000
VCID: 295E26E6806262099E-807C

Subsystem 1 - Part No: 8E0 941 329 A
Component: AFS-Modul links H04 0020

Subsystem 2 - Part No: 8E0 941 329 A
Component: AFS-Modul rechtsH04 0020

No fault code found.

End-------------------------(Elapsed Time: 06:57)--------------------------



            Address 01: Engine  (8E1 910 560 A)

19:18:17 Group 003: General
760 /min Engine Speed (G28)
3.50 g/s Mass Air Flow (G70)
2.7 % Throttle Valve Angle
10.5 °BTDC Ignition Timing Angle

19:18:17 Group 103: Fuel Injection (Fuel Pump Adaptation)
6.39 bar Current Fuel Pressure
-301 Fuel Pressure Regulator
121 Adaptation Value elect. Fuel Pump
Test OFF Fuel Pump Adapt. Status

19:18:17 Group 106: Fuel Injection (Fuel Pressure)
21.45 bar Fuel Rail Pressure
ON Electrical Fuel Pump

276.00 s Shut-Off Time



            Address 01: Engine  (8E1 910 560 A)

19:18:18 Group 003: General
760 /min Engine Speed (G28)
3.50 g/s Mass Air Flow (G70)
2.7 % Throttle Valve Angle
11.3 °BTDC Ignition Timing Angle

19:18:18 Group 103: Fuel Injection (Fuel Pump Adaptation)
6.46 bar Current Fuel Pressure
-336 Fuel Pressure Regulator
121 Adaptation Value elect. Fuel Pump
Test OFF Fuel Pump Adapt. Status

19:18:18 Group 106: Fuel Injection (Fuel Pressure)
21.27 bar Fuel Rail Pressure
ON Electrical Fuel Pump

276.00 s Shut-Off Time



            Address 01: Engine  (8E1 910 560 A)

19:19:06 Group 003: General
760 /min Engine Speed (G28)
3.69 g/s Mass Air Flow (G70)
3.1 % Throttle Valve Angle
7.5 °BTDC Ignition Timing Angle

19:19:06 Group 103: Fuel Injection (Fuel Pump Adaptation)
6.60 bar Current Fuel Pressure
-321 Fuel Pressure Regulator
121 Adaptation Value elect. Fuel Pump
Test OFF Fuel Pump Adapt. Status

19:19:06 Group 106: Fuel Injection (Fuel Pressure)
21.61 bar Fuel Rail Pressure
ON Electrical Fuel Pump

276.00 s Shut-Off Time



            Address 01: Engine  (8E1 910 560 A)

19:19:44 Group 003: General
760 /min Engine Speed (G28)
3.75 g/s Mass Air Flow (G70)
3.1 % Throttle Valve Angle
3.8 °BTDC Ignition Timing Angle

19:19:44 Group 103: Fuel Injection (Fuel Pump Adaptation)
6.40 bar Current Fuel Pressure
-314 Fuel Pressure Regulator
121 Adaptation Value elect. Fuel Pump
Test OFF Fuel Pump Adapt. Status

19:19:44 Group 106: Fuel Injection (Fuel Pressure)
21.92 bar Fuel Rail Pressure
ON Electrical Fuel Pump

276.00 s Shut-Off Time



            Address 01: Engine  (8E1 910 560 A)

19:19:46 Group 003: General
760 /min Engine Speed (G28)
3.64 g/s Mass Air Flow (G70)
3.1 % Throttle Valve Angle
8.3 °BTDC Ignition Timing Angle

19:19:46 Group 103: Fuel Injection (Fuel Pump Adaptation)
6.47 bar Current Fuel Pressure
-299 Fuel Pressure Regulator
121 Adaptation Value elect. Fuel Pump
Test OFF Fuel Pump Adapt. Status

19:19:46 Group 106: Fuel Injection (Fuel Pressure)
21.73 bar Fuel Rail Pressure
ON Electrical Fuel Pump

276.00 s Shut-Off Time