hello, i have successfully fixed the 1987 rx7, now when i drive and hit about 5000 rpms, the engine seems to rev back and forth by itself making the car jerk, what is my problem, also, i think i may have an exhaust leak, how do i check and fix it?

 

[quote name='mesallem' date='Apr 11 2005, 07:34 PM']hello, i have successfully fixed the 1987 rx7, now when i drive and hit about 5000 rpms, the engine seems to rev back and forth by itself making the car jerk, what is my problem, also, i think i may have an exhaust leak, how do i check and fix it?


[/quote]

Vac leak or Coolant temp sensor!