UK Car Repair: Vauxhall, vauxhall astra sxi, vacuum line

Question
Hey I have a Vauxhall astra sxi 06. Which is struggling to start in any weather but taken to Vauxhall but they say it's fine. Just woundered wat u think??

Answer
Leaking vacuum line from inlet manifold? check the line for leaks
Bad temp sensor?
Air lock near water temp sensor in cooling system?

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Have the error codes scanned at a parts shop, try to get it done under £20 and maybe for free if you phone around enough. There must be something,
When you have the codes, tell me what they are.