I have a B18B in my Si CRX and I have notice that it starts up fine but after a couple of mintues it idles up and down..like bogging. I have read other post and its says to check the FITV & the IACV but I have no idea what they are? Also what other things should I check for? I have the Hanes CRx book and still can't find what those things are. Any help will be appreicated! thanks!

 

iacv (behind the intake manifold, facing firewall)-remove the two bolts and clean the screen. fitv (below the tb)- disassemble it and bottom out the screw.
Also bleed your cooling system and check vacuum lines. Those steps should take care of your idle issue.

 

i bet you its the iacv, i would do both just to be safe though......its got 2 coolant lines going to it. clean the screen, but it may be bad so no matter how much you clean it, it may still do that....gl

 

It sounds like it is the FITV, mine was doing that surging idle thing to took of the FITV and tightened up that white plastic screw thing and it was fine.
By the way, your crx manual will not help you, you need to buy a manual for the car your engine came out of; ie integra manual for ls/gsr swaps or a prelude manual for h22 swaps. good luck.

 

also, if you need help on how to service the fast idle thermo valve, do a search, I did and found a good write up with pictures, helped out alot.