Have been researching low idle when cold and high idle when hot. Our v12 seems to be controlled by a spring in a valve under the manifolds. Had it all appart, possibly was seized, makes sense as water hoses were blocked with rust. Any way, now it’s been apart does any one know how to set it up, seems to be adjustable? What’s the electric plug do, I guess a sensor reading position of valve for fuel control to match air flow ?

 

G'day Stu,

Have a look in this publication starting at page 193 and in the Idle Control section you will find all the info on the idle control system of your car.

Cheers,
Jeff.

https://tinyurl.com/V12-ND

 

If it is your idle control valve you have 2 to compare with

Researching your electrical meter readings

B bank : at idle

Orange / Black color wire , 4.8 volts

Orange / Yellow color wire 9.8 volts

A bank :

Orange / Green color wire , 4.8 volts

Orange / Red color wire , 9.8 volts

Preffer to read it with connector still on as removing may change the engine out of idle behavior

Both valves are powered by fuse # 16 right engine bay fuse box as B + power and a single wire to them both through connector Papa Indy 1 ( position 5 ) and then there is a splice for the A and B side split

These would be B bank White / Orange color wire and A bank White /Orange ( same ) color wire on the control valves connector

pics coming




The White / Orange wire of interest is hidden in this pic

The Papa Indy 1 connector should be white but there are examples of both being black

There was a TSB on both these connectors getting corroded

 

With what information I can gather ......

I do not have the V - 12

At the connector ( it has to remain installed ) read for the B + volts dc on the feed wire X

The ECU will have a changing resistance ( inside it ) on the return wire passing through the coils in the control valve resulting in a change in resulting voltage at the test points

You have the other bank control valve to compare

You may have to warm up the control valve and tap on it to fail