Ok hi everyone i have a 2000 civic si that i have had for about 2months whats going on is speedo some times works but it like trips out and some days it will work fine and days it doesn't work the vtec doesn't work. But some times if its not working and your driving down the road and u rev the motor speedo will jump up and work? also at idle some times if you rev the motor speedo will move also? also my obd2 slot is working i take it to autozone or checker it wont read it says error? one last thing this happens randomly ill be driving on freeway in 5th gear going 65ish and motor just like kicks over all power is on but motor loses all power if u step on pedal it just bogs so i shut key off and turn on agian fixes the problem. sorry i know this was like 3 questions but please help im bout to take to shop and spend some cash. i just dont know if its speed sensor or vss people have said or wire ground problem?? haha

 

sounds like a speed sensor.

 

i forgot to mention its a jdm b16a with the stock si ecu.