[Crasher]

It is going into what is known as “limp mode” to protect the engine and this will have stored a fault code on the engine ECU...BUT it may not be an OBDII emissions code (a “P” code) so proper VAG specific diagnostic equipment will be needed to guarantee an accurate result.

 

[Crasher]

Unfortunately it is usually the high pressure fuel pump, do you know if it has had a fuel filter recently?

 

[Crasher]

Do you know (or can subtly enquire) if and how they purge bled the system before starting it or if they just did it the old way and cranked until it started?

 

[Crasher]

Not the correct method but it should be OK IF iit continued to run without stalling or even wobbling about, you are supposed to run the in tank pump (and electric high pressure pump fitted to some models) for about two minutes before starting or the mechanical high pressure fuel pump (HPFP) can run dry and so it eats itself as the hardens steel gear runs dry in the aluminum body which then throws ally particles through the system and into the injectors where it cannot be removed. Putting this right means completely cleaning the entire fuel system including the tank and electric pump(s) plus a new HPFP, inectors, timing belt kit and water pump and using genuine parts that is around £3500 plus labour.