3.0tdi fuel consumption dropped significantly - no fault codes

[grasshopper]

Hi All

The fuel consumption has dropped significantly on my 2012 3.0tdi A6 Avant.

Ive just got back from my garage who scanned it using his snap on unit.

The only thing that looks amis is:

'coolant temperature at radiator outlet' is showing 15.4 degrees C

The line underneath is:

'coolant temperature at radiator outlet - SPEC' and this is showing 93.5 degrees C

Couple of questions:

1. Is the 'coolant temperature at radiator outlet - SPEC' the expected value?

2. If the 'coolant temperature at radiator outlet' is low (15.4 degrees) would this cause the ECU to over fuel?

The coolant reservoir is certainly a lot warmer than 15 degrees so I can only presume this sensor is reading incorrectly....?

Thanks

[Olio]

What is your reference? When was that over? Last 2-3 weeks were really bad for fuel efficiency due to low temps.

[grasshopper]

What is your reference? When was that over? Last 2-3 weeks were really bad for fuel efficiency due to low temps.

This has happened steadily since about September last year.

When I used to fill the tank it would give me a range of 590-610 miles, this has steadily dropped to 460miles range now.

In reality, I was getting 560ish miles a tank, Im now getting 390 miles before the fill warning comes on.

Ive tried supermarket fuel, shell fuel, shell super diesel stuff and it doesn't make any difference.

Theres definitely something wrong...

[Olio]

Yes, it seems you're right. About the coolant temp, I read them like you. Expected temp 90+, read 15+

Maybe a sensor issue, or an air bubble in the system? (Cf Coolant temperature actual V specified value | Ross-Tech Forums (https://forums.ross-tech.com/index.php?threads/10364/) )

The 3.0 TDI avant is the car I should have bought I i had known better then ;)

[grasshopper]

Has anyone else any thoughts?

Or any experience of the snap on diagnostic unit?

Is the SPEC value the expected value?

[grasshopper]

Can anyone assist me in the part number for the radiator outlet sensor? I’m going round in circles searching for it and it’s interrupting my Saturday night beers 😬

Thanks

[Elansear]

This may assist.
Audi Parts catalog - ETKA Online, Audi EUROPA, original Catalog Audi EUROPA (https://audi.7zap.com/en/rdw/)

[grasshopper]

Thanks

[grasshopper]

Is the radiator outlet sensor 06A 919 501 A
Or is this the sender to the dash board?

Nothings ever clear or easy is it? :biglaugh:

[morski]

Thats the one. £46.80. Same one used across a lot of models. Interior temp sensor is on the dashboard and air temp sensor for engine management is on the front bumper bar

[grasshopper]

Thats the one. £46.80. Same one used across a lot of models. Interior temp sensor is on the dashboard and air temp sensor for engine management is on the front bumper bar

Thanks

Just to clarify - this is the sensor I need OR is this the one to the dash gauge (works fine, sits at 90 deg)

Whats it like to change? It is easily accessable?

[morski]

Cant say for sure that this is the sensor you need to fix your issue. Or where the dash gets reading from
Needs to be replaced from underneath the car. Loss of coolant is expected so you will need some more G12/13(check). Held in with a clip.

[grasshopper]

BUMP

Can anyone assist if this part number is the one required for the radiator outlet temp reading back to the ECU?

Thanks

[grasshopper]

Hi All

I have had the car scanned using VCDS tonight, please see results below...

Concerningly - theres no faults shown for the engine/coolant system, so Im none the wiser really....

Anyone have any ideas where to go from here?

Thanks

Friday,05,March,2021,17:28:35:41378
VCDS -- Windows Based VAG/VAS Emulator Running on Windows 10 x64
VCDS Version: 20.12.0.1 (x64)
Data version: 20201125 DS322.1
Ross-Tech: Home (www.Ross-Tech.com)




VIN: WAUZZZ4G3CN119173 License Plate: XXXX
Mileage: 186628km-115965mi Repair Order:






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




Chassis Type: 4G-AU57 (4G0)
Scan: 01 02 03 05 08 09 10 15 16 17 19 3B 42 44 46 47 52 53 55 56
5F 62 6D 72


VIN: WAUZZZ4G3CN119173 Mileage: 186628km-115965miles


01-Engine -- Status: OK 0000
02-Auto Trans -- Status: OK 0000
03-ABS Brakes -- Status: OK 0000
04-Steering Angle -- Status: OK 0000
05-Acc/Start Auth. -- Status: OK 0000
08-Auto HVAC -- Status: Malfunction 0010
09-Cent. Elect. -- Status: OK 0000
10-Park/Steer Assist -- Status: OK 0000
15-Airbags -- Status: OK 0000
16-Steering wheel -- Status: OK 0000
17-Instruments -- Status: OK 0000
19-CAN Gateway -- Status: Malfunction 0010
3B-Sensor Elect. -- Status: OK 0000
42-Door Elect, Driver -- Status: OK 0000
44-Steering Assist -- Status: OK 0000
46-Central Conv. -- Status: OK 0000
47-Sound System -- Status: OK 0000
52-Door Elect, Pass. -- Status: OK 0000
53-Parking Brake -- Status: OK 0000
55-Headlight Range -- Status: OK 0000
56-Radio -- Status: OK 0000
5F-Information Electr. -- Status: OK 0000
62-Door, Rear Left -- Status: OK 0000
6D-Trunk Elect. -- Status: OK 0000
72-Door, Rear Right -- Status: OK 0000

-------------------------------------------------------------------------------
Address 01: Engine (J623-CDUC) Labels:. 059-907-401-V2.clb
Part No SW: 4G0 907 401 F HW: 4G0 907 401
Component: 3.0TDI EDC17 H37 0005
Revision: 53H37---
Coding: 12254012052601020000
Shop #: WSC 02391 785 00200
ASAM Dataset: EV_ECM30TDI0114G0907401F 001005
ROD: EV_ECM30TDI0114G0907401F.rod
VCID: 2649C9A85946AFB458-8072


No fault code found.
Readiness: 0 0 0 0 0


-------------------------------------------------------------------------------
Address 02: Auto Trans (J217) Labels:| 0B5-927-156.clb
Part No SW: 4G1 927 156 B HW: 0B5 927 156 F
Component: 0B5 30 TDIRdW H10 0003
Revision: --H10--- Serial number: 0000001671
Coding: 000001
Shop #: WSC 02391 785 00200
ASAM Dataset: EV_TCMDL501 A02196
ROD: EV_TCMDL501.rod
VCID: 2C5D3B8047AA95E48E-8078


No fault code found.


-------------------------------------------------------------------------------
Address 03: ABS Brakes (J104) Labels:. 4G0-907-379-V1.clb
Part No SW: 4G0 907 379 H HW: 4G0 907 379 H
Component: ESP PREMIUM H09 0361
Revision: -------- Serial number: --------------
Coding: 27A68701E465E180DB00
Shop #: WSC 02391 785 00200
ASAM Dataset: EV_ESPPremiAU57X 004028
ROD: EV_ESPPremiAU57X_004_AU57.rod
VCID: 366919E889E6DF34E8-8062


No fault code found.


-------------------------------------------------------------------------------
Address 05: Acc/Start Auth. (J393) Labels:. 8K0-907-064-05.clb
Part No SW: 4H0 907 064 BP HW: 4H0 907 064 BP
Component: BCM2 2.0 H31 0333
Revision: 00002001
Coding: 05B92F06000000000000
Shop #: WSC 02391 785 00200
VCID: 78F5D7D0CB72E9443A-802C


Subsystem 2 - Part No SW: 4H0 905 852 C HW: 4H0 905 852 C
Component: J764 ELV MLB H39 0046
Serial number: 2311000279950014


No fault code found.


-------------------------------------------------------------------------------
Address 08: Auto HVAC (J255) Labels:| 4G0-820-043-2Z.clb
Part No SW: 4G0 820 043 H HW: 4G0 820 043 H
Component: KLIMA 2 ZONEN H10 0064
Serial number: 17011200040672
Coding: 3622000820
Shop #: WSC 02391 785 00200
ASAM Dataset: EV_AirCondiBasisUDS 002040
ROD: EV_AirCondiBasisUDS_002.rod
VCID: 244DD3A02F7A5DA446-8070


1 Fault Found:
0027 - Motor for Defroster Flap
B1090 07 [008] - Mechanical Failure
Intermittent - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 3
Fault Frequency: 1
Reset counter: 189
Mileage: 186461 km
Date: 2021.03.01
Time: 07:34:57


Voltage terminal 30: 13.02 V
Outside temperature: 2.5 ∞C
Inside temperature: 0.52 ∞C
Defroster flap motor-Act.val.: 11309
Defroster flap motor-Target value: 11252
Defroster flap motor-Stop open: 11294
Defroster flap motor-Stop closed: 10000




-------------------------------------------------------------------------------
Address 09: Cent. Elect. (J519) Labels:. 4H0-907-063-V1.clb
Part No SW: 4H0 907 063 BN HW: 4H0 907 063 F
Component: BCM1 2.0 H12 0111
Revision: 20012002 Serial number: 00000001202324
Coding: 2600201040349FE00181008300001D0CCF9DC7082709010100 0004602100
Shop #: WSC 02391 785 00200
VCID: 75EBDEE4DC60942C21-8020


Subsystem 1 - Part No SW: 4G2 955 119 HW: 4G8 955 119 A Labels: 1KX-955-119.CLB
Component: WWS57X 111210 H35 0051
Serial number: 111222020908
Coding: 0045F7


Subsystem 2 - Part No SW: 8K0 955 559 HW: 8K0 955 559 Labels: 8K0-955-559.CLB
Component: RLS H04 0003
Serial number: 20036344
Coding: 02512B


Subsystem 3 - Part No SW: 4G0 941 531 E HW: 4G0 941 531 E
Component: E1 - LDS H07 0044
Serial number: 12 01 2012 00001489


Subsystem 4 - Part No SW: 4G0 907 658 A HW: 4G0 907 658 A
Component: Humidity_Sens H02 0002
Serial number: 07584A06000000000001


No fault code found.


-------------------------------------------------------------------------------
Address 10: Park/Steer Assist (J446) Labels:| 4H0-919-475-7X2.clb
Part No SW: 4H0 919 475 N HW: 4H0 919 475 C
Component: PARKHILFE ACC H07 0050
Revision: 11001001 Serial number: 55901201702476
Coding: 080308
Shop #: WSC 02391 785 00200
ASAM Dataset: EV_EPHVA18AU57X0000 002005
ROD: EV_EPHVA18AU57X0000_002_AU57.rod
VCID: 3D7B06C4ACD00C6C29-8068


No fault code found.


-------------------------------------------------------------------------------
Address 15: Airbags (J234) Labels:* 4H0-959-655.clb
Part No SW: 4H0 959 655 C HW: 4H0 959 655 C
Component: Airbag10.43 H40 0040
Revision: -------- Serial number: 003JG006ABM1
Coding: 30323436313330303537554A305234473053
Shop #: WSC 02391 785 00200
ASAM Dataset: EV_AirbaAU10BPAAU64X 001014
ROD: EV_AirbaAU10BPAAU64X_VW51.rod
VCID: 366919E889E6DF34E8-8062


Crash sensor for side airbag: driver side:
Serial number: 3575HRB405311PNA58PD


Front Passenger's Side Airbag Crash Sensor:
Serial number: 3585HRB4067124B2BPV8


Rear Side Airbag Crash Sensor (on driver's side):
Serial number: 3515JRB405H12QE681E/


Passenger side rear thorax airbag crash sensor:
Serial number: 3525JRB4067134DMK0I+


Crash sensor for front airbag: driver side:
Serial number: 3554VRB405F0V8BO30N


Crash sensor for front airbag: front passenger side:
Serial number: 3564VRB405F0V8BOH0SF


No fault code found.


-------------------------------------------------------------------------------
Address 16: Steering wheel (J527) Labels:. 4H0-953-568.clb
Part No SW: 4G0 953 568 A HW: 4G0 953 568 A
Component: Lenks.Modul H05 0201
Revision: 00000000 Serial number: 20120121000583
Coding: 000035
Shop #: WSC 02391 785 00200
VCID: 30652FF06382F104B2-8064


Subsystem 1 - Part No SW: 4G0 951 528 A HW: 4G0 951 528 A
Component: E221 - MFL H08 0009


No fault code found.


-------------------------------------------------------------------------------
Address 17: Instruments (J285) Labels:| 4H0-920-xxx-17.clb-SRI1
Part No SW: 4G8 920 982 K HW: 4G8 920 982 K
Component: TDieGb H79 0416
Revision: 28460177 Serial number: 658090112593018
Coding: 33A610000B012600010000
Shop #: WSC 02391 785 00200
ASAM Dataset: EV_RBD4K 004045
ROD: EV_RBD4K_AU57.rod
VCID: 3C7D0BC0B7CA05641E-8068


No fault code found.


-------------------------------------------------------------------------------
Address 19: CAN Gateway (J533) Labels:* None
Part No SW: 4G0 907 468 G HW: 4G0 907 468 A
Component: J533--Gateway H08 0214
Revision: -------- Serial number: 00000000362296
Coding: 00CD077D00
Shop #: WSC 02391 785 00200
ASAM Dataset: EV_GatewUDS 001025
ROD: EV_GatewUDS_AU57.rod
VCID: 346D23E09F9ACD24D6-8060


Battery Monitoring Control Module:
Subsystem 1 - Part No SW: 8X0 915 181 HW: 8X0 915 181
Component: J367-BDM H07 0141
Serial number: 00000000003790748382


Voltage stabilizer:
Subsystem 2 - Part No SW: 8K0 959 663 B HW: 8K0 959 663 B
Component: J532_DCDCStab H05 0006
Serial number: 12011002452011200410


2 Faults Found:
12290 - Quiescent Current
U1406 00 [009] - Too High
Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 7
Fault Frequency: 254
Reset counter: 119
Mileage: 90824 km
Date: 2017.12.04
Time: 18:59:46


Voltage terminal 30: 12.3 V
Voltage terminal 15: 0.0 V
Control Module temperature: 9 ∞C
System status: LIN_active
IN ESP_standstill flag: no standstill detected
Engine running: OFF
IN ZAS_Te_X: OFF
Terminal 15 status via CAN: OFF
Terminal 15 status: OFF
Datenfeld: 0


12291 - Energy Management Active
U140B 00 [009] - -
[New feature! Extended UDS fault detail is only supported by current gen. interfaces]
Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 7
Fault Frequency: 1
Reset counter: 156
Mileage: 186628 km
Date: 2021.03.05
Time: 17:15:52


Voltage terminal 30: 11.4 V
Voltage terminal 15: 11.5 V
Control Module temperature: 17 ∞C
System status: Terminal 15 on
IN ESP_standstill flag: standstill detected
Engine running: OFF
IN ZAS_Te_X: On
Terminal 15 status via CAN: On
Terminal 15 status: On
Datenfeld: 1




-------------------------------------------------------------------------------
Address 3B: Sensor Elect. (J849) Labels: 4G0-907-637.clb
Part No SW: 4G0 907 637 HW: 4G0 907 637
Component: SARA 3D H02 0009
Revision: -------- Serial number: EJ1BPA32017TZS0
Shop #: WSC 00000 000 00000
ASAM Dataset: EV_SARA 009017
ROD: EV_SARA_009.rod
VCID: 6BDFF89C822452DCC7-803E


No fault code found.


-------------------------------------------------------------------------------
Address 42: Door Elect, Driver (J386) Labels:. 4H0-959-793.clb
Part No SW: 4G8 959 793 E HW: 4G8 959 793 A
Component: TSG FA H05 0212
Revision: -------- Serial number: --------------
Coding: 011F16204001620002080002
Shop #: WSC 02391 785 00200
VCID: 42817538DD2E739454-8016


No fault code found.


-------------------------------------------------------------------------------
Address 44: Steering Assist (J500) Labels:| 4G0-909-144.clb
Part No SW: 4G0 909 144 L HW: 4G0 909 144 G
Component: RCEPS H35 0010
Revision: 00001000 Serial number: 0006296816
Coding: 101000010000
Shop #: WSC 02391 785 00200
ASAM Dataset: EV_RCEPS 009008
ROD: EV_RCEPS_009.rod
VCID: 326125F8658EC314C4-8066


No fault code found.


-------------------------------------------------------------------------------
Address 46: Central Conv. (J393) Labels:. 4H0-907-064-46.clb
Part No SW: 4H0 907 064 BP HW: 4H0 907 064 BP
Component: BCM2 2.0 H31 0333
Revision: 00002001 Serial number: 0168447687
Coding: 013B0E2220B934018320090400030400000000000000000000 0000000000
Shop #: WSC 02391 785 00200
VCID: 78F5D7D0CB72E9443A-802C


Subsystem 1 - Part No: 4G0 951 177
Component: DWA-Sensor H01 0010


Subsystem 2 - Part No: 1K0 951 605 C
Component: LIN BACKUP HO H05 1501


Subsystem 3 - Part No SW: 3AA 962 243 HW: 3AA 962 243
Component: GEB.F.Heckoef H12 0719
Serial number: 84201259


No fault code found.


-------------------------------------------------------------------------------
Address 47: Sound System (J525) Labels: None
Part No SW: 4G0 035 223 C HW: 4G0 035 223 A
Component: BOSE-G3-C7 H07 0160
Revision: CJ007001 Serial number: 00000000018069
Coding: 010000
Shop #: WSC 02391 785 00200
VCID: 1D3BE64404106C6C09-8048


No fault code found.


-------------------------------------------------------------------------------
Address 52: Door Elect, Pass. (J387) Labels:. 4H0-959-792.clb
Part No SW: 4G8 959 792 E HW: 4G8 959 792 A
Component: TSG BF H05 0212
Revision: -------- Serial number: --------------
Coding: 011F16204001620002080002
Shop #: WSC 02391 785 00200
VCID: 41837A34D828688C4D-8014


No fault code found.


-------------------------------------------------------------------------------
Address 53: Parking Brake (----) Labels: 4H0-907-801.clb
Part No SW: 4H0 907 801 E HW: 4H0 907 801 A
Component: EPB-4 H03 0012
Revision: -------- Serial number: 00000000230934
ASAM Dataset: EV_ParkiBrake 001022
ROD: EV_ParkiBrake_VW51.rod
VCID: 2A513D984D5E8BD47C-807E


No fault code found.


-------------------------------------------------------------------------------
Address 55: Headlight Range (J431) Labels:| 8X0-907-357.clb
Part No SW: 4H0 907 357 A HW: 4H0 907 357 A
Component: ....LWR12.... H02 0013
Serial number: 120119-0004-034
Coding: 1122A6101000A300
Shop #: WSC 02391 785 00200
ASAM Dataset: EV_HeadlRegulBasic 005001
ROD: EV_HeadlRegulBasic.rod
VCID: 2C5D3B8047AA95E48E-8078


No fault code found.


-------------------------------------------------------------------------------
Address 56: Radio (R) Labels: Redir Fail!
Part No SW: 4G1 035 053 E HW: 4G1 035 053
Component: Radio U Basic H41 0093
Revision: AB001007 Serial number: 227A-0C7525665
Coding: 010003010000000001
Shop #: WSC 02391 785 00200
VCID: 2143DAB43868488C2D-8074


No fault code found.


-------------------------------------------------------------------------------
Address 5F: Information Electr. (J794) Labels:. 4E0-035-6xx-5F.clb
Part No SW: 4G0 035 670 G HW: 4G0 035 670 A
Component: H-BNT-EU H48 0484
Revision: -------- Serial number: 428AU0C7538401
Coding: 050101010003E1ED05008B3E00000003000001000000000000
Shop #: WSC 02391 785 00200
VCID: 2757C4AC564CB6BC63-8072


Subsystem 1 - Part No: 8R0 060 884 AH
Component: EUR 2012 1308


Subsystem 2 - Part No SW: 4G2 919 610 C HW: 4G2 919 610 C
Component: E380 BDT C7 H11 0204
Serial number: 90349LA30008E


Subsystem 3 - Part No: 8R0 060 961 C
Component: CD-Database 3638


No fault code found.


-------------------------------------------------------------------------------
Address 62: Door, Rear Left (J388) Labels:. 4H0-959-795.clb
Part No SW: 4G8 959 795 E HW: 4G8 959 795 A
Component: TSG HL H04 0212
Revision: -------- Serial number: --------------
Coding: 010F14204001620002080002
Shop #: WSC 02391 785 00200
VCID: 448D7320C73A7DA466-8010


No fault code found.


-------------------------------------------------------------------------------
Address 6D: Trunk Elect. (----) Labels:* Redir Fail!
Part No SW: 4G9 959 107 A HW: 4G9 959 107 A
Component: HDSG-Modul H03 0139
Revision: 14003001 Serial number: 013200518
Coding: 097205C010
Shop #: WSC 02391 785 00200
ASAM Dataset: EV_HDSGAu572 001001
ROD: EV_HDSGAu571.rod
VCID: 346D23E09F9ACD24D6-8060


No fault code found.


-------------------------------------------------------------------------------
Address 72: Door, Rear Right (J389) Labels:. 4H0-959-795.clb
Part No SW: 4G8 959 795 E HW: 4G8 959 795 A
Component: TSG HR H04 0212
Revision: -------- Serial number: --------------
Coding: 010F14204001620002080002
Shop #: WSC 02391 785 00200
VCID: 448D7320C73A7DA466-8010


No fault code found.


End-------------------------(Elapsed Time: 05:15)--------------------------

[lynalldiscovery]

Some random thoughts
1, was the car new to you last September?
2, is the tank taking the same amount of fuel it always did?
3, are all wheels turning freely or is any wheel running hotter than the others?
4, have you checked the air filter, and more importantly the silly mesh thing in the inlet trunking?

i can certainly see coolant temp sensor reading low effecting mpg figures, but no by the amount you are saying, unless you only do slow speed town work all the time.

[grasshopper]

Answers to your questions:

1. No, I’ve had car for 3 years. Used to commute 120 miles a day (motorway) but have changed jobs 18 months ago so do ‘fast’ A roads but only 20 miles a day. I noticed range dropped from 600 to 550/560ish
2. Yes it seems to. Not noticed anything different.
3. Nope, all ok there. All checked and ok.
4. I haven’t looked at the air filter or the mesh thing. Where abouts is the mesh thing?

Thanks for your assistance and suggestions 👍

[beemerboy9]

A drop from 600 miles to 550/560 represents a less than 10% difference. I would expect that transferring from motorway to A-roads.

Are you truly unhappy about the present fuel consumption?

[grasshopper]

A drop from 600 miles to 550/560 represents a less than 10% difference. I would expect that transferring from motorway to A-roads.

Are you truly unhappy about the present fuel consumption?

I accept motorway to a roads will give 10% drop. I haven’t questioned that for a second.

Nothing has changed in the last 18 months and I’ve gone from 550 miles per tank to 390.

The distances/type of driving hasn’t changed so surely there is an issue somewhere, don’t you agree?

[beemerboy9]

Sorry, I did not spot the 390.