Octavia mk1 noisy box and power loss

Hello everyone

Can anybody shed any light on some faults with my octavia it's got a funny jangly type noise sounds like back lash in the diff but not sure. Only happens really when in a ,1,2,3 & 4 not so much in 5 & 6th gear when you accelerate then lift off and if you dip clutch noise stops. Have changed the box oil today made no difference, also got Asr light coming on a jerk then a slight power loss but engine runs ok most of the time but can be right under powered sometimes and have to stop and start again, have checked and cleaned all wheel sensors today but made no difference, hade this fault for ages code reader says 4 faults

17672, 17675, 17678, 17669.

Pd inj unit exceeds reg range cyll 1,2,3,4

Have changed the inj wiring loom but still the same so now was thinking about maybe it got a duel mass fault hence the noise and causing some problem with with crank sensor

Any thoughts welcome Im fast out of ideas