when i started the car , the car revs up and down

it revs up to 2,000 rpm and then lets go of throttle and when it hits 1,000 rpm it revs up to 2,000 rpm and on and on and on ? anyone know whats happening to my car ?

 

vacuum leak
check all your vacuum lines sounds like one cracked or fell off.

 

I had the same problem with my civic. It happened to be the brake fluid resevoir cap. When I removed it to do the brakes, I replaced it and the reving problem went away. I then took it off and put it back on, and the reving came back but only for like 20 sec. I did this a few times and the same thing, I thought it was strange, but just figured there was some kinda vacum on that system too.

 

thanks guys im gonna go check on it now

 

:eh:

Could also be a MAP, EGR or IACV sensor prob. Or dirty injectors. Check your MIL.

 

The brake booster is all tied into the same system.

Could be anything from a bad throttle body gasket, to the pcv valve...

 

True the brake BOOSTER requires vacuum to function properly, but how would it affect the fluid reservoir of the master cylinder? If both functioned like you described, engine vacuum would bleed all of the brake fluid out of the car and draw it into the combustion chamber.

 

I seriously don't know. It was strange I admit, but it fixed the issue, so I am down with that.