Random turn off when driving car (not s2 , audi 2.0 abk )

[M2ki]

Relay nr. 30 under dash. Check for cracked solder joints.

[Mikes2]

on the abk that will be the ecu relay. well known issue

[willg54]

Just the engine or dash lights etc going off too?

My old 80bdid this, was the small earth connection on the battery.

[Sima Aron]

Engine randomly shuts off after hard driving . Spark plugs replaced , fuel pumps / filters replaced , lambda sensor replaced .

What could be the problem ?