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Q: I'm wondering what would cause my car not to stay when it is warm , I'm changing all pre and post cat sensors today. No power also

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Hello I'm having problems with my car, it has a lack of power, also will not start once it has reached normal temps, does not overheat. I've change all gaskets so they're are no vacuum leaks, my old reader tells me I'm lean in bank one and bank 2,idk what it could be, I'm changing pre and post sensors today, do you think an air box temp sensor could cause the no start warm issue? Thank you and sorry for not having proper punctuation oh and it ruins very rough until it's warm, then it kinda drives but feel very slow,

My car has 163000 miles.
My car has an automatic transmission.

A: Hello there, a variety of faults can cause ...

Hello there, a variety of faults can cause your 1996 BMW 740iL to not start when cold and run rough. Without knowing the exact code I can only give general advice. A lean condition can be caused by many faults such as low fuel pressure, failing fuel injector, a vacuum leak, oxygen sensors, or exhaust leaks. Before more parts are replaced this vehicle needs diagnosed so unnecessary repairs are not performed. A qualified technician such as one from YourMechanic will be able to perform a loss of power inspection on your vehicle and make any repairs required to get your vehicle driving normally again.

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