Changing crankshaft sensor...

[MellowP]

Hi all, my 07 220d developed a warm start ( or actually non start problem) this year. Generally doesn't matter but the it failed it's annual NCT (Irish MOT) as it wouldn't start at all. Local garage changed the fuel filter but couldn't find any fault. I plan to buy a new sensor and fit it, I've nothing to lose!.

2 questions: 1 do I have to take the air con compressor off and is this  a big job ( apart from refilling the gas)?  I'm moderately good with tool;s ( sparks, filters brake discs that sort of level).

2 what are the chances of this working??

Thanks in advance. Phillip