legacycentral bbs

Has anybody tried to just remove the stupid thing? Seriously what if we could just cover up the hole with a block off plate and adjust the idle with the one screw on the throttlebody. Does this seem feasible? The IAC seems like an unreliable. overy complicated way of controling idle. and it doesn't help emissions very much when my car has an overly rich 2,000rpm idle. So why is it there? That's my question -haha.

If you want to try this, I would leave the sensor in place but just electrically disconnect it. That way you still get the temperature-sensitive valve's functionality.

I don't think it'll help with your mixtures though.

guess i don't know much about the sensor itself or the emissions/feuling system. So it is controled by temperature and the computer both? Is the valve always letting air into the intake? Why does it exsist? In any case i'll unplug it tommorrow and report any interesting findings.

Indeed the mixture problem is probably from the fact that i have the knock sensor and O2 sensor unplugged. Or a bad MAF. I get code 49 (wrong MAF sensor), which is wierd seeing as the car runs fine and doesn't throw the code for abnormal MAF voltage.

It's not a sensor.

Have you read the FSM section about it and searched for old posts by me about it?

Try it....you're idle will shoot up to about 2000 rpm.

You need it there.

oh so it's not temperature-SENSEative

I'm not sure what you mean Josh. the idle is already at 2000 rpm when i start the engine cold.

The main idea here is that i'm looking outside the box/valve for a simpler way of controling the idle.
i don't want bimetalic temperature sensing material valves and learning computers to control my idle. i just want a screw. a screw can take a 300,000 mile beating and wont require $290 to replace. Emissions be damned if people can drive H2's then i can use a screw. How do older or less sophisticated cars achieve a smooth reliable idle anyway?

Most cars have some sort of idle control valve, even older or less sophisticated cars. Without the bimetallic valve you won't be able to regulate a higher idle at cold temperatures. That means you'll either have to idle high all the time or suffer through engine stalls when cold.

Our stock idle control setup is actually a fairly simple system. Many cars use stepper motors and stuff which complicates things a fair bit.

You may also want to look into fitting some kind of dashpot... our stock IAC valve takes the place of the traditional dashpot.

And if you use your A/C often but not all the time, you may also want to fit some kind of other fast idle device to increase airflow when the compressor clutch is engaged. The stock IAC valve provides that functionality as well.

Impregacy wrote:oh so it's not temperature-SENSEative

I'm not sure what you mean Josh. the idle is already at 2000 rpm when i start the engine cold.

The main idea here is that i'm looking outside the box/valve for a simpler way of controling the idle.
i don't want bimetalic temperature sensing material valves and learning computers to control my idle. i just want a screw. a screw can take a 300,000 mile beating and wont require $290 to replace. Emissions be damned if people can drive H2's then i can use a screw. How do older or less sophisticated cars achieve a smooth reliable idle anyway?

What's your idle like when warm? Is it that high?

Get the car at normal operating temp and pull the connector. You'll see what happens.

Air will always flow through the valve. The IAC valve has two sets of controls. The rotary valve controlled by the ECU, and the temperature sensing one.

You can't just use a screw. A screw can not compensate for cold start, or variations in engine load at idle.

Even carburators had those features.

i suppose you guys are right. how about if i comprimise and use a bimetallic screw?

A bimetallic screw?

NO