gotpie

I have a 95 200sx se-r, My problem is when I start the car its RPM goes to about 1500, when it warms up the RPM goes to about 1000. When I push the clutch coming to red light to stop the RPM drops to 400 to 500 and has staled ones. Now it only drops to 400 to 500 about 50% of the time. My check engine comes on every two week or so and it reads VSS sensor, and I replaced that sensor and reset the ecu. but I still have the same problem. . I searched this site for VSS and timing and idle problems nothing came close to my problem i'm having. I might not have spelled what I searched correctly and or I just don't know what to search. If someone knows what to search for or can help please tell me.

Slacky

id say off the bat to check for vacuum leaks, cracked vacuum hoses. if not that it could be a dirty IAAC