Used MQB car check with OBDeleven

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

Basic Faults Scan

As you expect - star with a simple full scan. This will bring fault codes from all the modules in the vehicle.

Do not clear found fault codes just yet!

Some amount of fault codes is nothing unusual. For example fault code B201A - SVM check. in 0x5F - Infotainment is expected if someone installed Toolbox, updated navigation maps, flashed newer firmware of the infotainment unit.

Uxxxx fault codes

Uxxxx code 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.

Another thing that can trigger Uxxxx code 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

EA888.3 TSI/TFSI Timing Chain Stretch

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 → Channel: Camshaft adjustment intake bank1, phase position

Module 0x01-Engine → Live Data → Channel: 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, 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.

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 → Channel: Camshaft adjustment, exhaust, bank 1, specified value

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

Intake side

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

Module 0x01-Engine → Live Data → Channel: 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.