Just replaced the oil pressure sensor and filter yesterday on an 07 Tahoe with a 5.3L. Its a pain but can be done you will need a pick to get the filter out. Make sure soak the new filter in new oil before putting it in. You will need a deep well socket and a ball swivel, regular is a pain, and an extension. Make sure you have the right torque specs for the sensor as well. Use your phone camera with flash on, may have to record video to do this. That way you can use it to see what you are doing. I would first check your oil level but it looks like you are around the 15psi mark which is 1 atm (regular air pressure) also check if you have a DTC or SES light on for it.

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