Turbo replaced with new now epc comes on and no boost

[Silverback]

Hi, my car is 2016 GTS 2.0 CULC engine (220ps). Turbo turbine shaft broke so had new Garrett turbo fitted by garage and now epc light comes on and she's not boosting properly.
Turn off and start again and light goes out but comes on again as soon as you want to accelerate.
The cruise control indicator light goes amber as well.
They tried going through master tech diagnostics who did some stuff remotely that was supposed to fix it, garage doesn't know what they did as the screen on their link went blank and when they asked the tech stated it was 'secret' !
Any one had this as its a pain having paid out the short end of £1700 to replace the turbo.

[Cuprabob]

EPC refers to the Electronic Power control, which is basically the fly by wire throttle system. The issue is probably related to either the throttle control motor / butterfly or the potentiometer in the throttle pedal or the wiring in relation to one of these. Possibly when the garage replaced the turbo they never plugged the connector to the throttle body securely.

Ideally you want to connect VCDS and identify the fault code that is triggering the EPC light and limp mode.

[Silverback]

Thanks for that. They use master tech which is essentially VAG's diagnostics for non VAG garages, costs them quite a bit for the licence and the MT people link directly into the diagnostics. apparently they got the garage to adjust some settings but it hasn't worked.
Its going back in on Tuesday but i'm a bit miffed that fitting a new Turbo has now led to another issue, hoped it was plug and play lol!

[Cuprabob]

Hope you get it sorted on Tuesday. Come back and let us know what it was.

[Silverback]

Yeah, will do. the car was running fine until I did the overtake to beat all overtakes and when the teurbo hit full boost it went pop, the car drove and bizarrely the EPC didnt come on as I assume the modules were still communicating despite there being no boost due to the broken shaft.
I've had a quick check on all connectors and they are all nicely secure. It's just a bit odd as it must be modules not talking to each other almost as if VW have a sneaky "you can't get a Turbo fitted by anyone other than us but at triple the cost" software cheat, but they wouldn't do that would they..........

[Silverback]

So , bit of an update. It appears that the throttle body and turbo actuator are not communicating properly hence the EPC light. Some coding today produced a very stepped, stuttery response form the actuator. The turbo supplier have agreed to supply a replacement turbo after some round robin arguing between them the on line coding people etc.
The turbo should be plug and play and as the EPC didn't come on when the turbine shaft broke it has been agreed there must be an issue with the control module on the actuator.
So a warranty job to be done but the garage can't fit it in for about 10 days so i'll report back.