In the Haynes repair manual it says that idle should be at 550rpm without the IAC valve connected, and 700rpm with it connected. Whats an IAC valve?

 

Idle Air Control valve

 

Where is it? Is it the valve on top of the intake arm going to the vacuum hose closest to the firewall on top of the throttle body?

 

top of the throttle body

 

no its on the back of the manifold the one with two coolant lines attatched to

 

excuse me, Misa is right, it also has a wire connected to it and its two vacuum lines
the fast idle control valve uses coolant temperature

 

i tossed my fast idle valve thats why my intake manifold is nice and cool to the touch

 

How does VTEC work?

 

 

like NaWZ mang!

 

*sigh*

 

Its like a NA Teurbough!!! LOL LOL LOL

 

Id like to see an acurate description of vtec in someones own words

 

Ok ok, getting back to IAC, I'm confused! Two coolant lines on the back of the manifold? I'm not really sure where this is that you are talking about. Can anyone explain a little better?

 

look on the back of the manifold which is facing the firewall, the tw coolant lines going vertically into the sensor is the IAC valve

 

I see, thank you. I will check it out.

 

if this helps anyone:
http://www.hondaautomotiveparts.com/...=THROTTLE+BODY

#19

 

Let me give it a try.

First, let's explain what VTEC does. VTEC (Variable valve Timing and lift Electronic Control) is a way for Honda motors to optimize power and keep fuel efficiency. The way it does this is by having two different cam lobe profiles to open the valves.

How does it do it? Well, it is relativly simple. Like stated before, a Honda Camshaft has two different sets of lobes. Each set of valves is actually operated by three different cam lobes. The smaller of the two lobes, which are palced on the outside of the larger one, operate the valves under normal driving conditions, and at lower RPMs. The cam lobe rides on what is called a rocker. The rocker then transfers its movement to the valve. the larger cam operates what is known as a follower. The follower does not touch any valves. It simply follows the higher cam lobe, which some refer to as the VTEC lobe or profile, until it is needed. Once the engine reaches a certain RPM the follower is brought into play. Oil pressure sends a locking pin through the follower and both rockers essentially locking them together. This allows the rockers to move with the follower which is riding on the higher cam profile. This in turn opens the valves more, for a longer duration, and at a slightly different time. This allows for more air and fuel to enter the combustion chamber for added power.


I hpe that works. Pardon any spelling, grammar, or puncuation errors. i was in a hurry.

 

I apologize Misa, I see and am reading what you are talking about, the valve actually operates by air but coolant temperature is what they control it with

 

all good man