ok i have a 1993 240sx that i just put a nismo high flow filter on an when i get to a high rpm it fells like the car is loosing acceleration than it will pick up that loose acceleration again than change gear(yes its an auto im gonna do a mt swap ) i dont know what the problem i i put on the mas air adapter and i have the intake temp sensor connected also i have no idea what the problem is!

 

Idle the engine and check for air leaks by spraying WD-40 on your intake, vacuum lines and injectors. If the engine bogs when you spray, you've got a leak.

Check the engine temperature sensors with a multimeter. Take resistance readings at low, moderate, and high temperatures. Resistance should be higher at low temperatures and lower at high temperatures.