2.0 TSFI multiple faults, VERY rough idle, and overheating exhaust. Advice?

[AJ97]

Hi, this isn't my vehicle, trying to help out a friend. Its a 2018 A4 2.0T ULTRA TFSI. The cars been parked and hasn't moved in around 8 months now from what they told me. The car has an extreme loss of power, and a VERY rough and unsteady idle. If I try to press the accelerator the car doesn't even let the engine rev, like it has some kind of limiter preventing it from accelerating at all. If I do press the pedal the idle actually becomes very steady and almost normal / smooth. There is a ton of warnings on the dashboard, including engine, drivers assistance, parking brake malfunction, among others. Exhaust has no smoke to indicate anything there, the coolant looks clear and non contaminated, top of the engine oil fill plug looks clear and normal, no foaming or anything like that. I have no way to check the engine oil level as they don't put dip sticks anymore and the MMI was refusing to show the level even after running for around 5 minutes.

Here's where I think the problem could be, during the short duration I had the car running to do the OBDeleven scan I noticed the exhaust shielding get extremely hot to the point it started glowing red. This was in the location where the oxygen sensor / turbo wastegate is located. Almost as if the exhaust is being blocked from exiting the engine block and it just continues to heat up and up. Could this be a failed waste gate or turbo?

Here's the OBDEleven full scan, I do have a HEX-NET from Rosstech, but because its the limited VIN version I didn't want to burn a vin use on this unless I decide to do the repairs for them so I opted for my OBDeleven for the time being.

---------------------------------------------------------------
Full scan
Control Units: 21
Fault count: 31
Control Units:
08 Air Conditioning
System description: Klima Zone 3
Software number: 8W0820043T
Software version: 0210
Hardware number: 8W0820043T
Hardware version: H60

Faults:
No trouble codes found

BC Rear Right Door
System description: TSG HBFS
Software number: 8W0959595H
Software version: 0129
Hardware number: 8W0959595F
Hardware version: 005

Faults:
No trouble codes found

02 Transmission
System description: 0CK 20TFSINAR
Software number: 8W2927155AH
Software version: 0002
Hardware number: 0CJ927156
Hardware version: H05

Faults:
No trouble codes found

09 Central Electrics
System description: BCM1 MLBevo
Software number: 8W0907063CB
Software version: 0267
Hardware number: 8W0907063BB
Hardware version: H13

Faults:
No trouble codes found

81 Gear Shift
System description: GSM-LL
Software number: 8W1713041G
Software version: 0077
Hardware number: 8W1713041J
Hardware version: H09

Faults:
No trouble codes found

BB Rear Left Door
System description: TSG HFS
Software number: 8W0959595H
Software version: 0129
Hardware number: 8W0959595F
Hardware version: 005

Faults:
No trouble codes found

5F Multimedia
System description: MU-P-LNS-US
Software number: 8W5035880D
Software version: 1320
Hardware number: 8W5035880
Hardware version: 034

Faults:
No trouble codes found

42 Driver Door
System description: TSG FS
Software number: 8W0959593H
Software version: 0129
Hardware number: 8W0959593F
Hardware version: 005

Faults:
No trouble codes found

17 Dashboard
System description: FBenUSA
Software number: 8W5920890G
Software version: 0377
Hardware number: 8W5920890G
Hardware version: H19

Faults:
No trouble codes found

16 Steering Column
System description: Lenks.Modul
Software number: 4M0907129GB
Software version: 0009
Hardware number: 4M0907129GB
Hardware version: H11

Faults:
No trouble codes found

6C Rear View Camera
System description: RVC Compact
Software number: 4M0980556A
Software version: 0250
Hardware number: 4M0980556A
Hardware version: H12

Faults:
No trouble codes found

A5 Driver Assistance
System description: BVS
Software number: 8W0907217C
Software version: 0050
Hardware number: 8W0907217C
Hardware version: H17

Faults:
U112300 - Databus error value received
static
Priority - 6
Malfunction frequency counter - 2
Unlearning counter - 4
km-Mileage - 84433 km
Dynamic environmental data - 028D42028573
date - 2023-10-09 17:58:07

U112300 - Databus error value received
static
Priority - 6
Malfunction frequency counter - 2
Unlearning counter - 4
km-Mileage - 84433 km
Dynamic environmental data - 028D4302857C
date - 2023-10-09 17:58:26

U112300 - Databus error value received
static
Priority - 6
Malfunction frequency counter - 2
Unlearning counter - 4
km-Mileage - 84433 km
Dynamic environmental data - 028D42028573
date - 2023-10-09 17:58:07

U112300 - Databus error value received
static
Priority - 6
Malfunction frequency counter - 3
Unlearning counter - 4
km-Mileage - 84433 km
Dynamic environmental data - 028D42028573
date - 2023-10-09 17:58:07


19 Gateway
System description: Gateway
Software number: 8W6907468F
Software version: 0123
Hardware number: 8W6907468E
Hardware version: H43

Faults:
U140B00 - Energy management active
Intermittent
Priority - 6
Malfunction frequency counter - 1
Unlearning counter - 44
km-Mileage - 84433 km
Dynamic environmental data - 038A00002A13012A140000
date - 2024-01-09 13:51:51

U140500 - Terminal 15
Implausible signal
Intermittent
Priority - 6
Malfunction frequency counter - 1
Unlearning counter - 42
km-Mileage - 84398 km
date - 2023-10-07 17:21:41

B191604 - Backup battery
Faulty
static
Priority - 4
Malfunction frequency counter - 76
Unlearning counter - 255
km-Mileage - 84433 km
Dynamic environmental data - 2AD00000
date - 2023-11-16 19:42:10


46 Comfort System
System description: BCM2 MLBevo
Software number: 8W0907064EC
Software version: 0387
Hardware number: 8W0907064DC
Hardware version: 025

Faults:
U112100 - Databus missing message
Intermittent
Priority - 6
Malfunction frequency counter - 255
Unlearning counter - 44
km-Mileage - 36901 km
Dynamic environmental data - 3A3E326C326C31FF175040040210028000000000009D009C01 00003C000100000001175500000000
date - 2021-09-21 13:31:48


44 Steering Assistance
System description: EPS_MLBEVO_ZF
Software number: 8W0909144H
Software version: 0410
Hardware number: 8W0909144B
Hardware version: H08

Faults:
U112300 - Databus error value received
static
Priority - 5
Malfunction frequency counter - 17
Unlearning counter - 4
km-Mileage - 84433 km
Dynamic environmental data - 4ED0252E630045000200017001528700000000000000000000 00000000000000000032
date - 2023-10-09 17:58:07


15 Airbag
System description: Airbag10.44
Software number: 8W0959655G
Software version: 0107
Hardware number: 8W0959655G
Hardware version: H05

Faults:
B13BCF2 - Multiple collision brake
No function
static
Priority - 2
Malfunction frequency counter - 2
Unlearning counter - 4
km-Mileage - 84433 km
date - 2023-10-09 17:58:22

B101629 - Frt.pass. side airbag disabled indicator lamp
Implausible signal
Intermittent
Priority - 2
Malfunction frequency counter - 1
Unlearning counter - 255
km-Mileage - 72693 km
date - 2023-04-08 14:53:58


01 Engine
System description: R4 2.0l TFSI
Software number: 8W0907115C
Software version: 0006
Hardware number: 06L907309
Hardware version: H12

Faults:
P15A500 - Engine oil level check
Implausible signal
Intermittent


P064200 - Sensor Reference Voltage "A" Circuit Low
static
Priority - 2
Malfunction frequency counter - 35
Unlearning counter - 255
km-Mileage - 84433 km
Engine speed - 0.00 1/min
Normed load value - 0.0 %
Vehicle speed - 0 km/h
Coolant temperature - 33 °C
Intake air temperature - 30 °C
Ambient air pressure - 1010 mbar
Voltage terminal 30 - 11.680 V
Dynamic environmental data - 209628107A0011BD0BED3EFC0512160EC41514031770000067 DA10100000
date - 2023-10-08 14:15:32

P00B700 - Engine Coolant Flow Low/Performance
Intermittent
Priority - 2
Malfunction frequency counter - 178
Unlearning counter - 255
km-Mileage - 83077 km
Engine speed - 814.50 1/min
Normed load value - 3.1 %
Vehicle speed - 0 km/h
Coolant temperature - 51 °C
Intake air temperature - 29 °C
Ambient air pressure - 1010 mbar
Voltage terminal 30 - 13.000 V
Dynamic environmental data - 209628441710F34418FFF8441A00004419029E441D4D2E441C 02B3
date - 2023-09-16 16:59:30

U061500 - Lost Communication With Engine Coolant Bypass Valve "A"
Intermittent
Priority - 2
Malfunction frequency counter - 254
Unlearning counter - 255
km-Mileage - 83075 km
Engine speed - 952.00 1/min
Normed load value - 4.3 %
Vehicle speed - 4 km/h
Coolant temperature - 102 °C
Intake air temperature - 56 °C
Ambient air pressure - 1010 mbar
Voltage terminal 30 - 12.800 V
Dynamic environmental data - 209628441708464418085C441A000044191635441D4D2E441C 02B3
date - 2023-09-15 20:49:39

P202600 - EVAP Fuel Vapor Temperature Sensor Circuit Low Voltage
Intermittent


P255700 - Engine Coolant Level Sensor/Switch
Circuit Range/Performance
Intermittent
Priority - 2
Malfunction frequency counter - 11
Unlearning counter - 255
km-Mileage - 83293 km
Engine speed - 822.50 1/min
Normed load value - 3.5 %
Vehicle speed - 1 km/h
Coolant temperature - 68 °C
Intake air temperature - 45 °C
Ambient air pressure - 1010 mbar
Voltage terminal 30 - 15.060 V
Dynamic environmental data - 20961644170A8F44180000441A000044190000441D4D2E441C 02B3
date - 2023-09-19 20:41:30

P268100 - Engine Coolant Bypass Valve Control
Circuit/Open
Intermittent
Priority - 2
Malfunction frequency counter - 120
Unlearning counter - 255
km-Mileage - 81846 km
Engine speed - 876.00 1/min
Normed load value - 3.9 %
Vehicle speed - 5 km/h
Coolant temperature - 103 °C
Intake air temperature - 51 °C
Ambient air pressure - 1010 mbar
Voltage terminal 30 - 12.840 V
Dynamic environmental data - 20961B4417084644180876441A00004419166D441D4D2E441C 02B3
date - 2023-08-12 16:20:56

P00B700 - Engine Coolant Flow Low/Performance
Intermittent


P021900 - Engine Overspeed Condition
Intermittent


P201500 - Intake Manifold Runner Position Sensor/Switch Circuit
Range/Performance
Intermittent


U013C00 - Lost Communication With Accelerator Pedal Module
static
Priority - 2
Malfunction frequency counter - 4
Unlearning counter - 255
km-Mileage - 84433 km
Engine speed - 0.00 1/min
Normed load value - 0.0 %
Vehicle speed - 0 km/h
Coolant temperature - 27 °C
Intake air temperature - 26 °C
Ambient air pressure - 1010 mbar
Voltage terminal 30 - 11.480 V
Dynamic environmental data - 209628107A0011BD0BAB3EFC0512160FE715140317700001EE C610100000
date - 2023-10-09 17:57:51


03 Brakes
System description: ESP9 Plus
Software number: 8W0907379Q
Software version: 0775
Hardware number: 8W0907379J
Hardware version: H10

Faults:
C105800 - Left rear tire
Tire pressure warning - too low
Intermittent


C105B00 - Right rear tire
Tire pressure warning - flat tire
static
Priority - 4
Malfunction frequency counter - 1
Unlearning counter - 255
km-Mileage - 77283 km
--- - 8300001B892400000000
Dynamic environmental data - 209628
date - 2023-06-03 20:21:27

C105A00 - Right rear tire
Tire pressure warning - too low
Intermittent


U122600 - Implausible engine control module
Intermittent
Priority - 3
Malfunction frequency counter - 2
Unlearning counter - 255
km-Mileage - 84433 km
--- - 74C00F00CA240050A080
Dynamic environmental data - 209628
date - 2023-10-09 17:59:38

U040100 - Invalid Data Received From ECM/PCM "A"
static
Priority - 3
Malfunction frequency counter - 14
Unlearning counter - 255
km-Mileage - 84433 km
--- - 73C00F00CA240000A080
Dynamic environmental data - 209628
date - 2023-10-09 17:58:07

C105400 - Left front tire
Tire pressure warning - too low
Intermittent


C105600 - Right front tire
Tire pressure warning - too low
static
Priority - 6
Malfunction frequency counter - 1
Unlearning counter - 255
km-Mileage - 77918 km
--- - 8200002A882400008080
Dynamic environmental data - 209628
date - 2023-06-21 14:41:39


52 Passenger Door
System description: TSG BFS
Software number: 8W0959592H
Software version: 0129
Hardware number: 8W0959592F
Hardware version: 005

Faults:
B122D29 - Lock unit for central locking
Implausible signal
static
Priority - 5
Malfunction frequency counter - 255
Unlearning counter - 4
km-Mileage - 76385 km
date - 2023-05-25 18:47:48

B122B13 - Central locking motors
Open circuit
static
Priority - 5
Malfunction frequency counter - 34
Unlearning counter - 140
km-Mileage - 73154 km
date - 2023-04-14 20:29:54

[kilroychile]

wow that is a lot of error

Is the battery full charged? it was 8 months without charging
Was the car las time running ok?
Seems to be a communication error because of the too multiple error at multiple modules

I would:
-Fully charge batteries
-Clear all codes after saving on a file
-review engine and cables not to be rusted, with humidity or damaged by a mouse
-review fluids level
BDW review all the car in physycal conditions
Then if is not ok, fix by parts, begining for the engine, then brakes, etc.

And westgate works to avoid too pressure, at idle should not affect

[AJ97]

Car was already like this prior to being parked for 8 months. It started doing this one day and they’ve left it ever since. I did ask if they ever had to jump the car or replace the battery at all before this happened to which they replied no. I asked that because of all the module faults and the energy management being active on multiple modules. The car had no issues starting up, battery was fine, brought a jumper pack with me for this reason but didn’t need to use it.

I think something is going on with the evaporate system, from my limited knowledge… Something is causing the exhaust pipe (the one the O2 sensor screws into) to heat up extremely hot, very quickly, which is putting the car into limp mode.