I put a new oil pressure switch in and now it won't start

Welcome to JustAnswer! You can ask unlimited questions to any of the 12,000 Experts! From doctors, lawyers, tech support, contractors, tutors, auto and boat mechanics, appliance technicians, veterinarians, accountants, appraisers, psychologists, engineers, heavy machinery masters, dream interpreters, and more, we've got you covered, 24/7. My name is \*\*\*\*\* \*\*\*\*\* I will be able to assist you. I’m sorry that you’re having trouble with your vehicle. Don’t worry though, we’ll be able to figure this out. Thank you for taking the time to let us help you out with this problem and hopefully we can sort it out quickly. Please understand that I do not know your knowledge or capabilities so I may need to ask questions to find out basic information to help solve your specific problem. Sometimes it may take a moment for me to respond because I may have to look up information about your concern. I appreciate your patience and will provide responses as soon as possible. The oil pressure switch wouldn't cause it to not start so you'll have to do some testing to see what it is. There are many possible causes for this problem. It could be faulty wiring, ignition system fault, module fault, fuel system problem, engine sensor failure, etc. To determine the problem you would need to use a scan tool that can read engine data and record data so you can see what specifically is happening. Is the fuel trim off?, is the crankshaft sensor signal gone?, etc. This would be the only way to figure it out. Without testing I would suspect that you are losing fuel pressure either because of a bad fuel pump or a problem with the wiring/module fault. If the check engine light is on, that would help out a lot because it could identify a specific fault. You would need to have the computer scanned to get the trouble codes stored in the module. If you can give me these codes, I would be able to pinpoint a specific cause for this problem. My goal is to give you the best service possible and to help you. If you have any questions or concerns, please don’t hesitate to let me know. If I’m not online at the time, I will respond ASAP when I get back.

Thanks

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