I am finishing up a B16a swap into a 90 CRX Si and for some reason the engine idles at 1800 even when warmed up. The engine runs good and has good power but it idles really high. any ideas. thanks

 

small leak or idle screw needs to be adjusted?

 

where would the leak be? my vacuums? and is the idle screw right above the butterfly valve?

 

Most likely the idle screw, its a quick and easy job just adjust it to your correct idle.

 

it could be your idle screw i suppose, but i wouldnt think it could be that outta wack to allow the engine to rev to 1800rpm, but i suppose i could be wrong. i would bet its a vaccum leak somewhere. or maybe your throttle cable is to tight and isn't allowing the throttle body to close completely.

 

well i replaced the vacuum sensor and turned the idle screw in all the way and it idles at like 700. so pretty good but doesnt seem right with the idle screw to the max. ill drive it for a little bit and see if its all good. if it isnt then isnt there a sensor for the idle that can be cleaned and where is it?

 

there is an idle air control valve (iacv) perhaps the seal isn't so great on it and its leaking. course if you havent ever had it off i wouldnt necessarily recommend removing it. without getting a new gasket you could very well make the problem worse. And i'd bet that although you got your idle down to pretty much where its supposed to be, it sounds like theres another issue, and forcing the idle down with the screw just kind of ignored the other problem as far as the engines concerned.

 

yes exactly i dont want to ignore the problom where is this sensor and is there a write up on how to clean it properly

 

yeah now its being stupid and it will sit at 2000 when i let off the gas then slowly go down to 1000 then it will jump it back up to 1500. its weird and dumb.

 

it sounds like your iacv is the issue. if cleaning it doesnt fix the hunting idle then maybe you should pick a new iacv seal from a honda/acura dealer.

https://honda-tech.com/zero...age=1

 

kk i can try that. it might help.

 

check your coolant level. park the car facing up hill, when the motor is COLD check the radiatior.

 

You have a vacuum leak. /thread.