Wastegate issue? 1.4 TSI 125PS Engine

[Amigo]

Hello all,

I wrote in the past in another forum on this site, but this is my first time in the VW forum, as it's about my wife's car.

The other day she told me that her Golf 7 1.4 TSI 125PS has shown the EPC light. I hooked up VCDS and this is what came up:
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Address 01: Engine (J623-CZCA) Labels:. 04E-907-309-V1.clb
Part No SW: 04E 906 027 HB HW: 04E 907 309 BH
Component: R4 1.4l TFS H25 2328
Revision: R7H25---
Coding: 0119007223441D082000
Shop #: WSC 00028 028 00029
ASAM Dataset: EV_ECM14TFS01104E906027HB 001004
ROD: EV_ECM14TFS01104E906027HB.rod
VCID: 6B9615CC82A611DECE-803E


CAN Converter 01:


2 Faults Found:
16432 - Charge Pressure Control Actuator
P334B 00 [036] - Mechanical Malfunction
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 2
Mileage: 50219 km
Date: 2020.06.23
Time: 08:33:33


Engine speed: 1565.00 /min
Normed load value: 8.6 %
Vehicle speed: 34 km/h
Coolant temperature: 90 °C
Intake air temperature: 42 °C
Ambient air pressure: 1020 mbar
Voltage terminal 30: 13.900 V
Unlearning counter according OBD: 40
Charge pressure actuator: specified position: 25.68 %
Bypass valve f high press turboch turbine inlet: actual value: 55.02 %
Charge pressure actuator: adaptation for lower stop: 3279.6 mV
Bypass valve for high press turbocharger turbine inlet: status-Bits 0-7: 0
Bypass valve for high press turbocharger turbine inlet: status-Bits 0-7: 0
Bypass valve for high press turbocharger turbine inlet: status-Bits 0-7: 7
Bypass valve for high press turbocharger turbine inlet: status-Bits 0-7: 55
Bypass valve for high press turboch turbine inlet: uncond volt: 1809.2 mV


16433 - Charge Pressure Control Actuator
P334B 00 [036] - Mechanical Malfunction
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 3
Mileage: 50035 km
Date: 2020.06.05
Time: 13:18:22


Engine speed: 2446.00 /min
Normed load value: 60.0 %
Vehicle speed: 37 km/h
Coolant temperature: 90 °C
Intake air temperature: 43 °C
Ambient air pressure: 1020 mbar
Voltage terminal 30: 13.099 V
Unlearning counter according OBD: 40
Charge pressure actuator: specified position: 25.68 %
Bypass valve f high press turboch turbine inlet: actual value: 49.72 %
Charge pressure actuator: adaptation for lower stop: 3279.6 mV
Bypass valve for high press turbocharger turbine inlet: status-Bits 0-7: 0
Bypass valve for high press turbocharger turbine inlet: status-Bits 0-7: 32
Bypass valve for high press turbocharger turbine inlet: status-Bits 0-7: 135
Bypass valve for high press turbocharger turbine inlet: status-Bits 0-7: 55
Bypass valve for high press turboch turbine inlet: uncond volt: 1637.2 mV


Readiness: 0000 0000
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I cleared the faults and then took the car for a spin on the motorway, and about 10 miles in the EPC light came up, got home and the same faults were logged. Interestingly, after a few hours I started the car again, no light, I drove it sedately for about 40 miles and light stayed off.

I had a look online for this and it seems that the wastegate rod tends to get stuck on the TSI engines. My wife's commute is through country roads, so the car very rarely gets a long run at higher speeds, when I assume that the Turbo needs to kick in and the wastegate to allow that to happen.

Is my inference correct in that my wife's use of the car did not require the Turbo to be engaged, and therefore the wastegate rod very likely got stuck?

I have the car booked in with my local independent garage, who are very good, so I am sure they will sort it out, but I was wondering if my assessment of the situation is plausible? Is the best course of action a replacement of the wastegate and the rod? Maybe someone else has experience of this? Thanks a lot!

[iMZee]

Turbos don't work like that...

For a waste gate to open the maximum turbo pressure set my the ecu needs to be exceeded. Most modern engines are designed for their turbos to be fully spooled with maximum pressure at low rpms to allow for a large amount of torque low down, hence how the new 1.5 tsi engine can hit 250nm at less than 2k rpm.

For it sticking, its 100 percent not the lack of use but i'd personally say something to do with its design which is causing the problem.

[Crasher]

Yes it is a very common problem, there is a factory technical bulletin about it.

[Amigo]

Yes it is a very common problem, there is a factory technical bulletin about it.

Thanks for that, what does the technical bulletin say?

[Crasher]

A seized operating arm.

[Amigo]

A seized operating arm.

I took the car to my local independent garage and they diagnosed it as the Turbo seized. They quoted me £750 for a new Turbo, wastegate actuator and arm, and a full oil change, plus the associated labour, which I think is not bad, for all that goes in it.