e-test problems

Took my car in for e test the first time, it had no egr Failed on Nox passed everything else.

took it in a second time with a hooked up egr , it failed on Hydrocarbons

anyone know what could have caused this? I didnt heat the cat up as much as i did the first time. and the ecu was changed but thats about it.

timing is 18 btdc