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This could be a few things. I would suggest checking to make sure the fuel pressure is within the manufacturer's specs even though the pump is basically new. Also, there could be a problem with ignition spark (bad crankshaft position sensor). Additionally, the second and third links show specifically how to check fuel pump pressure and for ignition spark. If the check engine light was on, you should check for trouble codes. That can point you in the right direction. The last thing I added was a link to a video which shows how that is done. If you find there are codes, let me know what they are and I can help direct you.
Take a look through these links. The discuss the possible issues and how to check where the problem may be coming from.
Let me know if this helps or if you have other questions.
Monday, August 20th, 2018 AT 8:28 PM