You changed the chains without changing the oil????It appeared after a cold night (-3°c).
I've found that P0302 -> cyl2, P0304 -> cyl4, P0306 -> cyl6. All are on the same bank.
I cleaned the wiring. P030 maybe appear as soon as some of them appears.
P1670 seems to be related with fuel pump.
She stayed parked 3 months with low fuel (1 bar and a half) during works.
I'm thinking of adding 20 liters of fuel just to see. If water cames in that doesn't sonds good, does it?
I was planning to change oil that has 15kkm on wednesday. Do you think this crappy oil could start P0018 and the oil change make it dispear? i wish...
Thanks a lot