ECU failure lamp flashing / contact garage message came on once - no codes

[golfed]

07 2.0 TDI 140 estate - accelerating hard - there was a massive "jolt/bang" the ECU warning lamp started flashing with the "contact garage" message. Went into limp mode immediately. Restarted engine - fault light cleared and it drives normally with no loss of performance or nasty noises. Have a cheapo code reader - no engine codes logged.

I replaced the tank lift pump myself about 150 miles beforehand - no apparent problems from that but might be related?

Turbo whistles a lot but has done so years with no loss performance.

Anyone got any ideas? Should I ignore it?

[martin1810]

Sounds like you over boosted and dropped into limp mode. Cycling the ignition resets this. You won't get a code until it happens more often or for longer.