My mass airflow sensor went out. changed that with a sensor that I know works. The fuel pump is also brandnew. When accelerating the car, it hesitates. Also has an rough idle and the car jerks when sitting at a light or when stopping. What could be the problem?

SOURCE: will not stay started or will run rough after starting. We have changed plug, fuel pump/strainer & mass airflow senscor

is the motor a qg18de if so think u have same problem as me and its the veriable cam timing sprocket on intake cam stuck in full advance wich is 25 degres

SOURCE: 2000 Xterra hesitateing, backfireing, not accelerating above 20mi

Airflow sensor very well may cause it , and Throttle position and temperature sensor too.
All of it has to be checked with good scaner , that can monitor values and data from ECM.
You need to find a better shop.

SOURCE: '97 Nissan pickup truck mass airflow sensor malfunction?

mine did the same thing except i bought one from python and it worked fine for 3 days but the same problem came back

SOURCE: Vehicle: 1998 Nissan Pathfinder

Hello,
When the MAF on most vehicles reach a point of preventing the engine from starting, you can usually just unplug it and the engine will start. If that doesn't work-
You may want to try having the O2 sensor, ( Oxygen sensor ), checked. It works with other components of the emission system and can cause similar symptoms as the MAF, including preventing the engine from starting.

Donnie

Testimonial: "Other similar issues are the cam position sensor, which is located inside the distributor. It's easier to just replace the distributor."

SOURCE: car stalled and will not restart

It is possible to have fuel pressure and have injectors that are completely closed. There are light testers that plug into the injector harness to check the pulse to open an injector. Available at autoparts with Tool loaner program.

Try starting fluid to see if it wants to run, If it does, then injectors are not opening, then find cause like camshaft sensor. At that point, like other Expert said, it could be Vacuum leak.

Will not turn over can mean several things. Is it cranking? Is it engaging and not moving the engine? If the starter is not moving then you have to go through the interlocks with brake pedal and shifter. But these work after the engine runs and would not cause it to stall.

Try the starting fluid and see if the spark is working, then shift to fuel delivery if it tries to start.