A3 Sportback (sport) 2.0TDI 140 Fault Codes (55 plate)

Hello all

Just after some advice really........
Had a light come on on my dashboard about 3 months ago (engine management light). Took it to a local garage with some diagnostic kit and the guy reset the light as he couldn't find a meaningful code. The light came back on almost straight away and has been on since. About two weeks ago, the traction control warning light has come on also. The button to turn off the traction control (ESP Sport?) will not now function (as I assume the traction control is off).

Took it back to the same garage again and the guy got the following two codes out:

01435 - Brake pressure sender 1 not valid
19559 - intake air pressure actuator

He tried to clear the codes but neither would.
I have continued to drive the car. I don't seem to be getting any reduction in performance - car picks up as it always has done. Still getting about 55mpg on decent motorway runs. No problems shutting engine off.

My questions are two fold really...
1 - do I really need to do anything about these 'faults' if there doesn't appear to be anything wrong? (apart from traction control not working - I will just keep the car away from the wife...:-))
2 - Is there anything I can do myself to try and fix? I did try a bit of web research and found a few snippets of info. I have checked fuse '8' as apparently, that can sometimes blow and cause one of the faults. I also have checked brake lights and all OK there.

Car is a 55 plate. Has done just shy of 100k - owned from new.

Thanks in advance