Used MQB car check with OBDeleven

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Check for clocked mileage indications, excessive wear symptoms, common mechanical faults, maintenance negligence in MQB-platform based and other VAG vehicles.

This writeup is based on my experience with Audi S3 (8V) and VW Golf MK7 (5G), but those methods should apply to other vehicles as well, depending on vehicle equipment and stored data.

I'm including both EA288 TDI Engine and EA888 TSI/TFSI engine methods for vehicle checks and diagnostics.

Please keep in mind, that below procedures were put together by me and this is not an official guide or fail-proof method of checking a vehicle. If you have suggestions, improvements, or want to share your own methods, please contact me.

Basic Faults Scan

As you expect - star with a simple full scan. This will bring fault codes from all the modules in the vehicle. You can use OBDeleven, VCDS, CarScanner OBD2 app, XTool, Launch, or any other diagnostic interface that can communicate with VAG vehicles.

Do not clear found fault codes just yet!

Function Restriction due to Insufficient Voltage

An example of U1400 code is related to low voltage which happens mostly on engine start. If the car battery capacity, SOC, or SOH is low, it can cause voltage drops that are considered to be deep enough to report them as a DTC fault.

Checking Software Version Management

Some amount of fault codes is nothing unusual and nothing to be worried about. For example fault code B201A. in 0x5F - Infotainment is expected if someone installed MIB Toolbox, installed navigation maps, updated firmware of the infotainment unit.

Function Limitation due to Received Malfunction Value

Example code U1113 can indicate that the module received a fault information from another module, that it relays on. So for that module it's a remote fault code. For example if there's an issue with one of the wheel speed sensors connected to the ABS module, the ABS module will have the "master" fault code, and all other modules that relay on vehicle speed data provided by ABS module, will have Uxxxx fault code stored.

Databus Missing Message

Another thing that can trigger example code U1121 is not properly configured module. If coding/adaptation was altered, module was replaced, or other module is no longer present in the car, it can cause a "missing message" fault code. It simply means that module is expecting some information from other module but it's not getting it.

Mileage Confirmation

Freeze Frames

When a fault code is triggered, there might be a related freeze frame stored with conditions details from the moment that fault code appeared. Although this data is intended to help troubleshoot the fault, it might also contain vehicle mileage information.

Automatic Gearbox

DSG mileage vs Engine mileage

DSG / S-Tronic / PDK gearbox mileage details can be found in TCU Live Data. Compare ECU and TCU mileage. 

Module 0x02-Gearbox → Live Data → Current vehicle odometer reading

Module 0x02-Gearbox → Live Data → Transmission mileage

Module 0x02-Gearbox → Live Data → Driving strategy transmission mileage

DSG Clutches mileage vs Engine mileage

Module 0x02-Gearbox → Live Data → Kilometerstand Kupplungs-Reibwertmodell

Infotainment Display operating hours

It's safe to assume that the infotainment display is on pretty much all the time when the engine is on. Display Unit stores its operating hours counter, which can be view in Live Data of the Infotainment System (Audi MMI, VW Composition and Discover, Porsche PCM, Skoda Swing/Bolero/Amundsen/Columbus, Seat Navi...). 

Module 0x5F-Infotainment → Live Data → Multimedia display unit 1 → Operating hour counter

Based on that readout we can estimate a rough mileage of the vehicle. For example, readout of 1500h can be multiplied by an average speed of 40mph / 60km/h. This would give an estimated mileage of 60k miles / 90kkm.

Notice: 40mph / 60km/h is an average speed in mixed conditions. For urban conditions I use 20mph / 30km/h, and for highway conditions 60mph / 90km/h.

Notice: if at some point display unit was replaced with new one (warranty repair) or used one (MIB retrofit), this calculation will not be valid.

Common Faults

EA888.3 TSI/TFSI Camshaft Adjustment Actuators

Camshaft adjuster is driven by oil pressure and and controlled with an magnetic actuator. Both intake and exhaust actuators are the same, and can suffer from the same issue, which is slow reaction causing idle RPM fluctuations, misfires, or even engine stall.

In ECU live data you can find specified and actual positions for both camshafts. By comparing specified and actual position, you can check if the adjuster is working correctly or not. You can check the difference on various RPM, but on idle it will be visible the most. 

Exhaust side

Module 0x01-Engine → Live Data → Camshaft adjustment, exhaust, bank 1, specified value

Module 0x01-Engine → Live Data → Camshaft adjustment, exhaust, bank 1, actual value

Intake side

Module 0x01-Engine → Live Data → Camshaft adjustment, intake, bank 1, specified value

Module 0x01-Engine → Live Data → Camshaft adjustment, intake, bank 1, actual value

In a correctly working engine, the difference between specified and actual should be ±1.00°. If the difference is reaching ±5.0° or higher, it will indicate failing actuator or failing adjuster oil valve.

EA888.3 TSI/TFSI Thermostat Actuator

TODO

TSB → https://static.nhtsa.gov/odi/tsbs/2019/MC-10166730-0001.pdf

Settlement → https://static.nhtsa.gov/odi/tsbs/2022/MC-10214802-0001.pdf

More Settlement details → https://waterpumpsettlement.com/Home/portalid/0

EA288 Diesel water pump shutter

TODO

EA288 DPF soot and ash levels

Both 1.6TDI and 2.0TDI engines are equipped with DPF. To simplify: DPF collects soot during the drive, burns it off every now and then, accumulates ash which slowly fills the DPF. You can check how much ash there is in the filter to estimate its state-of-heath. 

Module 0x01-Engine → Live Data → TODOOO

Front Radar (ACC, PreSense, FrontAssist) misalignment

Front-facing radar has a tolerance of ±0.8° variation from the perfect 0.00° setting. While driving, radar analyses the environment and can deduce if it's misaligned and by how much. This can be checked in radar module Live Data. 

Module 0x13 → Live Data → Misalignment angle, horiz.

Module 0x13 → Live Data → Correction angle

Values greater than ±0.8° will throw a fault code and radar-releated functions will not work. But values close to ±0.8° can indicate that the front end of the car was disassembled or the geometry of the car is slightly off.

DSG DQ200 Clutch Slip

DQ200 gearbox clutch was designed in such a way, that the clutchpack is engaged when there's no hydraulic pressure applied on it. This means that the transmission control module is very limited when it comes to the maximum pressure on the friction plates.

DSG DQ381 Auxiliary Pump issues

TODO

Heavy Usage and Neglected Maintenance Indicators

EA888.3 TSI/TFSI engine

ECU Flash Counter

TODO

EA888.3 TSI/TFSI Timing Chain Stretch

EA888.3 miles vs phase graph
EA888.3 miles vs phase graph;
source: https://www.audizine.com/forum/showthread.php/712531-THE-Timing-Chain-Tensioner-Failure-Thread?p=13449797&viewfull=1#post13449797

1.8TSI/TFSI and 2.0TSI/TFSI engines that you know from VW Golf MK7 (5G) Alltrack, GTI, R, Audi A3/S3 (8V), Skoda Octavia MK3 (5E) RS, and many other VAG vehicles have a timing chain which wear can be estimated from engine live data. Actually, ECU is estimating it itself, most likely based on the readouts from crankshaft and camshaft sensors. 

Module 0x01-Engine → Live Data → Camshaft adjustment intake bank 1, phase position

Module 0x01-Engine → Live Data → Camshaft adjustment exhaust bank 1, phase position

from 0.00 to -1.00 = perfect readout
from -1.00 to -4.00 = expected in a used vehicle
from -4.00 = chain most likely stretched and should be replaced/

Freshly replaced timing chain should report value between 0.00 and -1.00.

Based on user reports[1], every ~20k miles / 30kkm adds -1.00 to the camshaft phase position. For example: value -2.75 would indicated asdf of mileage 55k miles / 82kkm.

Chain that's stretched beyound a single tooth (jumped a tooth) will show value beyond -5.86.

There's much more reliable way of checking the stretch, by looking at the chain tensioner via the inspection window.[2][3]

EA888.3 TSI/TFSI Misfire counter

Module 0x01 → Live Data → Misfires per 1000 revolutions of cylinder *

Module 0x01 → Live Data → Numb. of misfir. cylinder *

Module 0x01 → Live Data → Misfires per 1000 revolutions of cyl. * intake manif. injection

If the misfire is noticeable and you can see above counters to increase while the engine is running, it can indicate issues with:

  1. low quality of fuel
  2. wear on spark plugs
  3. wear on ignition coils
  4. weak ground connection on the ignition coils

EA888.3 TSI/TFSI knock counter

Module 0x01 → Live Data → Todooo

If the engine knock is noticeable and you see above counters to increase while WOT acceleration, it can be caused by:

  1. too high combustion chamber temperature
  2. low quality of fuel
  3. overboost
  4. bad ignition timing

EA288 TDI engine

ECU Flash Counter

TODO

Diesel Injector correction

TODO

DSG gearbox

TCU Flash Counter

TODO

Gearbox Over-rev and Over-temp memory

TODO

Launch Control counter

DQ250 and DQ381 are capable of doing Launch Control. 

Module 0x02-Gearbox → Live Data → TODOOO

DSG Drive Modes statistics

D/S/M 

Module 0x02-Gearbox → Live Data → Driving strategy driving potions in *

Module 0x02-Gearbox → Live Data → Driving strategy transmission mileage

DSG Over-rev statistics

TODO 

Module 0x02-Transmission → Live data → "Analysis 101" (Betreibszeit Motor (Drehzahlbereich *))

DSG mis-shifts

TODO 

Module 0x02-Transmission → Live data → Analysis 103 → Anzahl nicht erfolgreich einlegevorgänge *-Gang

Haldex and LSD systems

Over-temp memory

Both Haldex and Limited SLip Differential modules check the friction plates temperature and store information about high temperature and overtemperature state. 

for Hadlex 4x4 (example VW Golf MK7 R, Audi S3 8V)

Module 0x22-AllWheelDrive -> Live Data → Duration of overtemperature

Module 0x22-AllWheelDrive -> Live Data → Upper Limit of Temperature Duration

for Limited Slip Differential (example VW Golf GTI PP, Skoda Octavia RS)

Module 0x32-DiffLock -> Live Data → Duration of overtemperature

Module 0x32-DiffLock -> Live Data → Upper Limit of Temperature Duration

Haldex front vs rear wheels speed difference

One of the information that you can see in 4x4 live data, is the speed difference between front and rear wheels. Most likely this is checked by the Haldex module to determinate if the 4x4 drive should engage the clutch-pack. 

TODO

By looking at this data you can check two things:

  1. While traveling with constant speed, if the difference is 0. If not it would indicate that one of the axis have wheels with smaller circumference.
  2. While accelerating with WOT (when the clutch-pack should engage), if the difference goes to 0.00. If not, it would indicate that the haldex system is not engaging or that the clutch is slipping.

Gateway module

Drive Select statistics

Module 0x19-Gateway → Live Data → TODOOO

Battery condition

TODO
  1. ↑ https://www.audizine.com/forum/showthread.php/712531-THE-Timing-Chain-Tensioner-Failure-Thread?p=13449797&viewfull=1#post13449797
  2. ↑ https://www.custompcguide.net/paul-timing-chain-guide-mk6-ea888/#visual_check_timing_chain_tensioner
  3. ↑ https://postimg.cc/jnfqmx1d
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