2024年5月23日 · The manufacturer of my RHD ITBs recommends using an idle air control valve, but with a throttle position sensor and Alpha N tuning rather than MAP and speed-density. The ECU controls the IACV duty cycle and has a table to control fueling based on the IACV duty cycle.

2018年3月20日 · IACV design for ITBs? I'm in the process of CADing up an ITB manifold to mount Toyota AE101 throttles on a Mazda BP (how original). I intend on gun drilling a chamber across all four throttles to provide MAP, IACV, and ports for brake booster, evap canister, etc. I originally measured up the OEM Mazda IACV and have been turning it every which way.

2020年1月21日 · Use MSExtra firmware and go with ITB mode to blend Alpha-N and MAP modes for better tuning across the range. It uses MAP at low throttle openings and lower speeds and Alpha-N for larger opening and higher speeds.

2022年12月21日 · Don't have the throttle plates set so the idle speed you want, makes it so the stepper IAC is in a closed position. Stepper motors are an open loop device, and will stall and lose steps, or position when run into solid stops, such as the IAC seat.

2008年6月29日 · The IAC is basically a solenoid controlled valve that bypasses the butterfly plate in the throttle body. When you are sitting at idle, the ECU opens the valve so some air gets into the motor and you don't stall out.

2006年12月18日 · The IAC in effect does the same thing as your foot on the accelerator, it lets air in and that's all your throttle does. The computer reads the engine speed and the MAP sensor reading and looks st the fuel table (or map) and decides how long to hold the injectors open.

2024年1月23日 · The ITB’s come standard with idle bleed screws or alternatively you can swap out with 8mm barbed fittings to run to an idle air control manifold/motor. The only way to deliver air from an IAC motor to the backside of the butterflies is via these barbed fittings.

2020年2月16日 · The one farthest from the IAC valve is for incoming air (I added a small filter to a short length of hose) and the other port is the air outlet, controlled by the valve. This gets routed to the intake for idle air.

2013年5月6日 · I just changed over to using idle control feature and understand what you are going through ( my old manifold was a hilborn ITB with no provisions for IAC valve or stepper motor control).....

2016年8月27日 · If it doesn't work as well as I'd like I'll add MAP and/or IAC. Is there a port at the front of the chamber? You might want to try moving the IAC or MAP connections to see if the problem cylinders move, and would be a way to verify your theory.