shuts off on freeway or underload 3500 rpms

[piapetpower]

My 240 sx shuts down when it get to 3500 rpms up hill or under a load. Has a new speed sensor. Not more than 3 months old. It also drops it's idle when steping on gas after a stop. Than sometimes it has a hard time starting. You have to turn it over while steping on the gas. The car will shake like crazy. It will final start after a few seconds. All of this happen just now and than. The speedometer goes crazy thats when the car seems to shut itself off. Than once it slows down alittle it kicks back on. I think it may be a short. My boyfriend thinks its the computer. Why just sometimes? Please any input may help. Thanks

[piapetpower]

My 240 sx shuts down when it get to 3500 rpms up hill or under a load. Has a new speed sensor. Not more than 3 months old. It also drops it's idle when steping on gas after a stop. Than sometimes it has a hard time starting. You have to turn it over while steping on the gas. The car will shake like crazy. It will final start after a few seconds. All of this happen just now and than. The speedometer goes crazy thats when the car seems to shut itself off. Than once it slows down alittle it kicks back on. I think it may be a short. My boyfriend thinks its the computer. Why just sometimes? Please any input may help. Thanks

[piapetpower]

My 240 sx shuts down when it get to 3500 rpms up hill or under a load. Has a new speed sensor. Not more than 3 months old. It also drops it's idle when steping on gas after a stop. Than sometimes it has a hard time starting. You have to turn it over while steping on the gas. The car will shake like crazy. It will final start after a few seconds. All of this happen just now and than. The speedometer goes crazy thats when the car seems to shut itself off. Than once it slows down alittle it kicks back on. I think it may be a short. My boyfriend thinks its the computer. Why just sometimes? Please any input may help. Thanks

My 240 sx shuts down when it get to 3500 rpms up hill or under a load. Has a new speed sensor. Not more than 3 months old. It also drops it's idle when steping on gas after a stop. Than sometimes it has a hard time starting. You have to turn it over while steping on the gas. The car will shake like crazy. It will final start after a few seconds. All of this happen just now and than. The speedometer goes crazy thats when the car seems to shut itself off. Than once it slows down alittle it kicks back on. I think it may be a short. My boyfriend thinks its the computer. Why just sometimes? Please any input may help. Thanks

[onosqv]

first off, is the Check Engine Light on? if so, go pull your codes. If you don't know how - go to 240sx.org -> FAQ's -> ECU or ECM codes. Or search button.

One problem at a time, when did it start doing this? As soon as you bought the car, or after some mod/maintenance?

Have you checked all your sensors? checked for leaks? etc? Have you done any maintenance on the car? Checked the spark plugs, wires, cap? bad tank of gas?