Hi Guys its me needing help again.
Scoob has just failed its MOT on emissions. CO2 is really high when revved, lower at idle but still a fail. Lamda was also high at first but then dropped down to a pass after some messing.
Before test noticed that one of the hoses to the dump valve was leaking boost under acceleration. This was fixed then reset ECU. This helped a lot but still failed, does it take the ECU some time to settle down? Could the leaking boost pressure make a big difference?
Any other ideas?
Car is a MY96 jap classic, only known mods being apexi dump valve and HKS pipe.
Cheers Ste