Blue smoke and engine codes

[1.6mk4GOLF16v]

blue smoke when i rev it, smells like theres alot of unburn petrol in it or maybe burning to much petrol, over fuelling perhaps?

codes that came up were:

16804 - catalyst system bank 1, effeciancy below threshold
            P0420 -35-00--
17811 - EGR system, regulation divergence
            P1403-35-10
17566 - Manifold pressure sensor (G71): implausible signal
            P1158-35-10

[rockmonkey69]

Too much fuel otherwise known as running rich gives black smoke not blue, your burning oil too, this might be the reason your catalytic converter is potentially blocked up.

[1.6mk4GOLF16v]

ive decat my exhaust pal, any other ideas?
is there a way to check lamba in bank 1? (manifold)

[rockmonkey69]

Your 16804 is more than likely the result of having a decat. You can run some logs to check if it's working. Mind I would be more concerned about the blue smoke though.

[Wayne]

Blue smoke is oil being burnt so you have problems with valve stem seals or piston rings.

[1.6mk4GOLF16v]

Blue smoke is oil being burnt so you have problems with valve stem seals or piston rings.

cheers guys will look into it asap