When I start my car my car, there is a clicking noise coming from the area of the iacv. It will do it for a good 3-5 sec. I have heard other people's maxes do the same thing. Also, when I give the car and little gas or rev it a little(below 2000 rpm), the idle will stay up for 3-4 sec. or so before it starts to go down ( it does the clicking think at the same time). Do it need to replace it, clean it, or is a normal thing and I am being paranoid? Anyone else have this going on?

 

I have a messed up IACV, but mine ticks constantly. Even when the engine is turned off. You might try cleaning it, can't hurt anything.

 

I guess I will try to clean it first, but I think it is shot.

 

Thing that gets me is that if the part is not working we should be getting a check engine light. This makes me think that the IACV may be fine and is just clogged. At least I hope so because I have read they are over $100.

 

The clicking is the stepper motor that controls it working. It's perfectly normal to hear it.

Your idle hang time can be adjusted. The throttle body set screw needs to allow the throttle plate to close a bit more. That will stop your idle from hanging up high like that. Only go 1/4 turn at a time, then test drive it for a while to see how it runs. The set screw is located down on the bottom of the throttle body right under the linkage. It's the stop screw that the main throttle lever sits on. You need to back that screw out to allow the throttle plate to close a bit more.

 

Good info, that is one I did not know. Now why in the heck would my stepper motor keep clicking in and out after my enigne is turned off. If I have the key turned to "on" it will click forever. ????

 

thanks man, I was thinking the clicking could be normal because I've heard it on som many other maximas, I will try adjusting the idle hang time.

 

well....I tried to adjust the hang time like you said and it didn't do a thing. I even backed the screw out far enough so that the throttle lever wasn't even sitting on it... and idle still hangs. anyone else have any ideas want it could be? If my IACV was bad, would it cause this?

 

It didn't work? Thats a first.

Is your throttle cable to tight?

I30 - The reason you hear it click away when the key is ON and the engine is off is because it's trying to adjust your idle speed. My guess is it doesn't know your engine is not running yet. When you first start your engine, that valve opens up to get a good start, then slowly closes (tic tic tic) to bring your idle speed down a bit.

I've tweaked my throttle body adjustments so much that I've got a start that only revs up to 1350 RPM's and sinks back to 1200 as a fast idle speed. In D cold my car idles at about 850, hot at 600. My hang is at about 650-700 for a second when I come to a stop, then settles to 600 again. I never feel my car pulling me at idle time, hot or cold. The ECU may also need time to adjust to any changes made to the throttle body. Give it some time and play with it a bit. Don't make any drastic changes, wait a day or so as you tweak it to really see how it runs both hot and cold.

 

The stepper motor has a cone with a swirl, or vortex pattern on it. The swirl pattern is made of small raised ridges on the plastic cone. I completely disassembled and cleaned my IACV assembly a couple weeks ago and found this cone boogered up with carbonized blow by deposits. I cleaned the cone with a toothbrush and choke cleaner,then carefully picked out more remaining stubborn deposits with a dental pick. I also cleaned the rest of the aluminum IACV metering block, including the FICV valves.

My car didn't have trouble starting before or have idle problems, but I did notice that afterward the idle steps from cold to hot idle were more distinct. Better off idle power and about 1mpg added after the cleaning too.