VL Walkinshaw Build Electronic Issues

['quipt4it]

The IAC does this so you won't get a stall condition.
How low do the revs drop after it kicks in?
You still may have to perform those checks in the circuit I posted.
I don't think it's A/C pressure related.

[Gareth]

I agree, A/C pressure is irrelevant

[Nzer]

I got it to idle ok. Then turned the A/C on.
https://vimeo.com/491498077

Why does it idle well in Diagnostic mode?
https://vimeo.com/491508087


Is this normal for the IAC to do this in diagnostic mode?
https://vimeo.com/491497762

['quipt4it]

The extra load is likely exacerbating the hunting.
I read in the IAC diagnostics if you disconnect the harness connector at the IAC that coil A and coil B should have a pulsing voltage.(diagnostic terminal earthed). Looks normal.
If connected, the valve will pulse in and out continuously.
Maybe read the diagnostics?

['quipt4it]

Just thought...dial back the IAC orifice (what size do you have it at now), and bump the throttle screw.
I did say it will need a balance between the two.

[Nzer]

The extra load is likely exacerbating the hunting.
I read in the IAC diagnostics if you disconnect the harness connector at the IAC that coil A and coil B should have a pulsing voltage.(diagnostic terminal earthed). Looks normal.
If connected, the valve will pulse in and out continuously.
Maybe read the diagnostics?

Yea I will have a good read.
It just bugs me how I can not touch any of the sensors (TPS reading 0.8v) and put it in diagnostic mode and it I’ll idle and rev all day!
I know that’s not the answer.

[Nzer]

Just thought...dial back the IAC orifice (what size do you have it at now), and bump the throttle screw.
I did say it will need a balance between the two.

In the vids I haven’t even changed the orifice. I was just checking the timing again to see what I had it at. I’ve adjusted to sit around 12.
That’s why I had the plug bridged. I sit in the car thinking why will it idle like this and as soon as I pull the bridge wire it goes all over the show. Sorry with myself not being very electronically minded I can’t understand it.

['quipt4it]

Try it and see...
I don't think the IAC comes into it in diagnostic mode. The diagnostic says the valve pulses in and out.

['quipt4it]

Is the IAC operating in diagnostic mode.
I wonder what would happen if you disconnected the IAC then started it. You said the throttle blade was open a fair bit. It may be enough to keep it running.
Your exhaust must be fairly loud if you said it was too late to start
Never stopped me

With the IAC unplugged the idle is high. That’s with both TB’s completely closed. I’ll get a video of it.

Yea it’s pretty reasonable and the garage is attached to the house. 9pm start ups I’m being a bit of an arsehole Dad.

When I said disconnect the IAC, did you pull the hose? I meant unplug the harness connector.

[Nzer]

Is the IAC operating in diagnostic mode.
I wonder what would happen if you disconnected the IAC then started it. You said the throttle blade was open a fair bit. It may be enough to keep it running.
Your exhaust must be fairly loud if you said it was too late to start
Never stopped me

With the IAC unplugged the idle is high. That’s with both TB’s completely closed. I’ll get a video of it.

Yea it’s pretty reasonable and the garage is attached to the house. 9pm start ups I’m being a bit of an arsehole Dad.

When I said disconnect the IAC, did you pull the hose? I meant unplug the harness connector.

Correct unplugged the electrical plug to the IAC.