I am currently using MPX5500DP for a simple arduino car counter - it measures the change in pressure of a sealed tube when a car drives over it.
The readings from MPX5500DP are not precise enough however; which sensor would I be able to get a more precise reading in ambient outdoor temperatures?
The MPX5500DP have a pressure measurement range from up to 500kPa, which, from my personal point of view, seems high for your kind of application. For more precision, I would recommend to use a smaller pressure range sensor so you can have higher voltage on the output when the car drives over the sealed tube.
You can start testing using the MPX5100DP, which is a very similar sensor to the MP5500DP, but with smaller measurement pressure range (0 to 100kPa).
MPX5100DP datasheet: https://www.nxp.com/docs/en/data-sheet/MPX5100.pdf