when i start the car the motor revs up and down by itself, from 1000 to 2000 back to 1000 and again and again, it does not go away even after i've been driving for a while.

 

i got the same problem with my car and posted a thread about it, got no help.

 

Hmmm check if your car is throwing any codes.

It might be a sensor or something acting up.

Also I know on my old Accord LX-i when that would happen I would have to check the vacuum lines and what not.
Also there are a few things that might be wrong with a EGR valve or something.
There is another one, but I can't remember the name.

Sorry this isn't much help.

If I do come across something, I'll be sure to post it.


Good luck