Hi

 

when I remove the IAA (Air Idle Control Valve)connector and measure the resistance across the "poles" of the IAA unit,

should there be a steady resistance there, and if so, what should the resistance be?

 

:o)

 

Maz

Okay

 

I can´t tell you if the connector is giving off 14 Volts when the engine is running as I took the Balance bar off for easier

access to the Air Regulator Valve.

 

I can tell you that the resistance of the valve is 0 ohm, in fact the multimeter Shows me it´s a closed circuit.

Okay

 

I can´t tell you if the connector is giving off 14 Volts when the engine is running as I took the Balance bar off for easier

access to the Air Regulator Valve.

 

I can tell you that the resistance of the valve is 0 ohm, in fact the multimeter Shows me it´s a closed circuit.

 

Hi Maz,

Sounds like you may have found your problem, I will try and explain my understanding of how the air regulator valve works.

Fundamentally it consists of a rotating disk that either opens or closes the valve, It does this in 2 ways. Firstly, when the engine and ignition is off, ambient temperature holds the valve open via a bi metal strip so as to allow air to enter the plenum during a cold start. Thus raising the idle.

Once the engine is started, a voltage of 14 volts is applied to the internal heater for approximately 5 minutes causing the bi metal strip to close the valve completely.

At this point, the only valve that is responsible for the idle is the IAA valve.

 

There is a simple check that can be done to prove that the valve is the problem. Once the engine is up to temperature, simply pinch the pipe between the IAA valve and the air regulator valve so as to close it off and you will see your RPM drop.

 

If as you say, there is no resistance found to the heater, then it sounds like the valve will not be closed. It may fluctuate a little depending on engine temperature but basically it will need replacing.

 

ps I should have said that the heater should take up to five minutes to close the valve completely, but the voltage will remain constant while the engine is running. This will keep the valve closed untill such time you restart from cold.

Edited April 30, 201312 yr by redwine300

Redwine

 

Thank you for an excellent description of the workings of the Air Regulator valve and the air control valve, for the first time I actually understand

what each part does, spot on mate!

 

Replacement parts are on their way (hopefully) will Keep you posted on Progress/ outcome

 

and again, thanks alot, it´s much appreciated.

 

:)

Any updates?

Sorted

 

Sorry about the huge delay, but I had to destroy the engine on the wifes car before i could start on the Z.

 

Redwine, you were spot on mate, Changed the Air Regulator Valve and the revs now drop to around 750 -800 rpm.

 

Thanks for all your assistance, it´s greatly appreciated.

 

:o)

Great to hear you have a happy zed mate.

Glad I could have been of some help mate!

 

Don't forget the rep' lol

 

Dave.