DesiredNameTkn

2019 M157 with Stage 1 Eurocharged ECU flash tune and 2nd cat delete. Getting intermittent CEL throwing P0299 code. Occurs even when I flash the ECU back to stock. Car does not feel underpowered or drive differently when light is on. Took in to the dealer but CEL was off (of course). Per SA turbos and exhaust all looked good. I used the code reader to clear the code, but it comes back. Anyone have ideas?

PeterUbers

Don't you need a tuner to code out the CEL from the egr fault if you have cat delete?

alternatively you have a turbo leak and they haven't found it yet

kponti

Boost solenoid or the vacuum hose that goes to the solenoid

cocobeex

^^^^ This is 99% is the cause.
Been there before.
Or one of the vacuum hoses is cracked.