hi there, first off admins forgive me if this is in the wrong spot, ok i hav a 1990 Integra GS and when i start the car it runs fine for about 3 seconds and then i'll get this werid reving and i'll rev up and down until i shift the car into gear and then it'll stop but as soon as i shift back to park it'll start again and it's affecting my car's stereo's system too so i'm guessing electrical now some people told me to replace the rad cap and i kinda found that werid but i tried it and that did nothing so please help me someone! any help is greatly appreciated

 

i have the same problem with mine and i have been told a few things
1. vac leak which i think mine is
2. the throttle cable is too tight
3. might be a sensor of some sort

mine is from the cc line possibly so best thing to do is dick around with it and try and source the problem

 

Chances are it's either the FITV (fast idle thermo valve) or the EACV (electronic air-control valve a.k.a. IACV). Both are easy to remove and either clean (for EACV) or tighten (FITV). If you don't have a service manual, do a search and you'll find a walk-through somewhere.

 

^^^i might have to look at those thanks