Throttle body fuel injector
 

I have a throttle body fuel injector (Rotec Engineering) installed on an ECi O320
160hp engine. It will not idle below 900rpm without engine quitting unless I activate primer. Anyone with knowledge of TBIs that could help would be appreciated. Thanks

Rotec
 

Idle bypass mixture circuit may be clogged or slide closing stop may have moved? These need carb heat if I remember.

I had essentially the same problem. Had to send it back to Rotec for repair--mine was a manufacturing defect. They fixed it under warranty (but you have to pay the shipping costs under their policy).

http://www.rotectbi.com/Installation.html
My son has one of these on his RV-4. It works great!
He did spend some time adjusting the idle mixture screw, which is behind the slide throttle actuator, so a low profile tool is a help.
Once set up, it has been a reliable and accurate fuel metering device that works with inverted flight.