i have a 99 civic w/ b16a4 swap... i have a coolant leak comming from a sensor thingy thats right under my throttle, its not on the block, its right under the throttle body.... *ITS NOT ON THE BLOCK, not the bypass, nor the thermostat, or the heater hose... leak is located right under the throtle lever

anybody know what sensor thats called, it has a small hose connect to it..

 

bump

 

It's the IACV. Check for coolant leaks from the rubber seal between the throttle body and IACV, and also from the two coolant hose connections to the IACV.

 

its fixed now it was actally the fast idle valve

 

Yup, FITV - fast idle thermo valve.