It might surprise you to learn, but we aren't psychics here.

Your car won't start. Does it turn over, and fail to start ? Is there anything at all when you turn the key ? Has this light been on for a while ? Has your car been kept well maintained ? Have you checked the oil level ?

Answers to those questions are a first step. Without that lot, then nobody on here has got a chance.

Hi My car won't start because the oil pressure sight came out on my dash board please tel me what is the problem

Based on the information you have given, it's the nut behind the wheel....

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