Ok, so the 1uzfe swap is done, but it does some weird stuff. It won’t idle. And that’s controlled by an Idle Air Control Valve. It wont idle 90% of the starts. But 1/10 starts, it will idle, and when it does, It idles great. But once you start driving it, if you push the clutch in, it will die. Rarely will it idle on its own after revving or driving.
A bit of info on the IACV: when power is first applied to the Ecu and the engine is started, the Ecu tries to sort out the home (fully open) position of the IACV. The service manual dictates the engine may take a few starts until the engine sorts out the IACV position. After that, the Ecu needs a full warm up to move the IACV through each position (I have performed this several times, including reapplying power).
Everytime the engine is turned off, the MREL Ecu output continues on to help the IACV return to home position. I can not verify this is happening, but I do know it is getting the voltage from MREL.
Here’s some info and wiring: 
So, preliminary checks: I cannot verify voltage present at the IACV (referred to as the ISC in diagrams). I can’t get meter leads into the molex due to the location in the engine bay, location of the molex, and lack of being able to have the valve out, molex attached, and the motor running, and the meter leads in place. Also, I’m a one man operation.
What I have been able to do is verify that the B/R wire (sensor power feed) does get 14vdc at all the other sensors, including those three VSV’s. So I am going to assume the IACV is getting power.
This leaves, finally, a dirty IACV. Sadly, the ‘93 year engine had the IACV that DOESNT have the removable motor. So I can’t internally clean it, like so many have done in the past. I don’t hear any “clicking” from the motor when the car is shut off.
The valve is a PITA to get out. The part new or reman is about 600$, an unknown condition eBay IACV is 50$. It’s my next step.
Thoughts?
