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Q: How do I know if my car needs a fuel pump?

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It's won't crank right up tales a couple of times to crank and when it gets to 30 mph it hesitates to go faster
My car has an automatic transmission.

A: Hello. Typically a fuel pump can fail in a ...

Hello. Typically a fuel pump can fail in a number of ways. Most of the time they simply go bad and the vehicle will no longer run. In other cases the pump can fail and not hold fuel pressure in the system which can make the vehicle hard to start. This is what it sounds like it going on with your vehicle. To diagnose this I install a fuel pressure tester and check to see if the system holds pressure when it is turned off. If not then you either have a bad pump, injector or fuel pressure regulator. If it holds pressure then the issue is in another system. If you want to have this starting issue looked at, consider YourMechanic, as a certified mechanic can come to you to [diagnose why the vehicle takes a long time to start] https://www.yourmechanic.com/services/car-is-hard-to-start-inspection

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A: Hi there. The sure way to determine if the ...

Hi there. The sure way to determine if the fuel pump is failing is to perform a fuel pressure test, both active and residual. The residual pressure test determines if this is the cause of extended cold start cranking. A faulty battery or starter could be causing the multiple cold crank attempts that fail. A proper test on the battery and starting system will reveal if there are any faults to cause this. There are several things that could cause the vehicle to hesitate as you've described: low fuel pressure, vacuum leaks, throttle body concerns, map sensor failing, airflow meter failing, etc.. I strongly suggest having a qualified technician perform inspections for the hesitation and hard starting to avoid replacing unnecessary parts. Your Mechanic has several available technicians that can assist you with a car is hard to start inspection and a car is hesitating inspection.

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