hey i got a b18c1.... drives fine but in nutral it tends to rev uip and drop... as soon as it drops it will rev up tho.. it will rev at 2000 drop to 1000 then rite back to 2000 then about 2 seconds later does the same thing again.. i have heaRD it ccan be jsut a plate on the intake that needs tightened but i really dont know so if some one could help me out that would be awsome..

 

It could be a vacuum leak or low coolant. I had this problem before on past cars.

 

could also be IAC valve $$$. Typical on ALL hondas. ahem Acuras.

 

air leak or alternator.

 

With it being a honda, it's most likely the IAC. I have the same problem last year, and it turned out to be the thermostat.

 

check the coolent level before you do anything that will happen with low coolent

 

I've had wonky idle issues but not as bad as yours. It was the cap and rotor.

Also I had my throttle cable was too tight and loosening it to spec helped.

The rotor screw had come out, been flung around, shattered my dust shield. The rotor popped off when I removed the cap.

Have a check:
Anatomy of a B-series Distributor - Team Integra

Advanced Ignition Troubleshooting - Team Integra

 

definitely check the vacuum lines first, though - i had one pop off when i was doing other work in the bay and i didn't even notice it.

if you need another IACV i have an extra.

peter