Idle air control valve question

Post by **Falkdesigns** » Tue Jul 13, 2004 5:59 am

Guys, Q45tech, I have a question. Last week on Wednesday morning I get in the car and start to go to work. I hear a whirring/whining sound, kinda high pitched. It wasn't doing it before, so I drive to work. It still did it and still does (I went out of town on Thursday, and just got back last night). Last Wed's I stop at my garage on the way home and we isolate the sound to be coming from the IAC. Can this be cleaned out, or do I need to replace it? Car has currrently 82k on 98 Q45t. Thanks!

Post by **elwesso** » Tue Jul 13, 2004 5:59 am

The only way I could see the IAC whistling or something is if the gasket has a small crack in it... The gasket is really cheap and shouldnt take long to replace or anything like that.....

BTW.. Did you ever get rid of those rims on the Q???

Post by **natsoundup** » Tue Jul 13, 2004 5:59 am

Is it easy to take off the IAC and clean it? I bought a gasket some months ago...but haven't had the energy to go in and take a look.... any piranahaas lurking back there?

Post by **Q451990** » Tue Jul 13, 2004 5:59 am

No problem at all unless you break the hose that feeds it - then it's a plenum job. You might pull the two retaining bolts, push it back toward the firewall, and then soak the hose junction with some WD-40 or silicone lubricant to ease getting the hose loose.

Heath

Post by **Falkdesigns** » Tue Jul 13, 2004 5:59 am

That's what I'm thinking, the gasket has a small crack, we used a stethoscope to isolate the sound, and it's def the IAC. We popped the hose off and the sound stopped instantly. So I guess I'll get a gasket and see if that cures it.

Wes, I still have the rims. I actually saw them in alloy at a local wheel shop. I'm still waiting to get the tires since I'm doing some vehicle wraps in exchange for the tires.

Post by **elwesso** » Tue Jul 13, 2004 5:59 am

At 120k my hoses were as new and I regret wasting $60 on those 2 [insert censored curse word here] IAC hoses... The Y shaped one and the other one thats like an inch long and costs $25.....

They freaking ROB you on hoses!

Post by **natsoundup** » Tue Jul 13, 2004 5:59 am

When my IAC started sticking on my Ford Expedition, the dealer came up with a price of about 525 dollars. I bought the new part for 55...unbolted two bolts and put it in without getting dirty.

That's a ripoff. The real sad part is that I probably could've cleaned the carbon with some carb spray.

BTW, the dealer said it took a lot of work to scrape off the gasket.LOL....

Post by **Falkdesigns** » Tue Jul 13, 2004 5:59 am

Yeah, I already popped the front one off and it came off easy. My car also looks as new under the hood, under the car, the suspension, brakes, etc... One thing that's definitely great out here, no snow, or salt and harldy any rain, so everything stays like new with minimal effort. Just dusty, but I wash it every week and spray undercarrige and wheel wells/suspension off well.

Post by **elwesso** » Tue Jul 13, 2004 5:59 am

Kev.. IF your still interested in selling the rims let me know.....

Post by **Falkdesigns** » Tue Jul 13, 2004 5:59 am

No prob Wes, I will be selling them as soon as I get tires for my other wheels.

Post by **Falkdesigns** » Tue Jul 13, 2004 5:59 am

So I'm taking it in tomorrow to put the new gasket on and keeping my fingers crossed the gasket will do it, I don't want to buy a 300 dollar part and have to wait longer to get tires for my new rims!!

Post by **Falkdesigns** » Tue Jul 13, 2004 5:59 am

Allrights, it's not the IAC, it's a small, vaccum powered piece above the throttle body and IAC. It's held on by 2 phillips screws, has one vaccum hose and a plunger with an adjuster nut that stops the throttle from closing too fast and holds it at a set close spot. I got a picture diagram from South Bay Infiniti, and you can see the part, but they don't offer a number and they guy in parts didn't know what it was called. Anyone, Q45tech?? We figure that the diaphram inside it has a small hole which is causing the noise. However, the noise is much much softer than it was and in some cases I can barely hear it. Friends have told me I should work in the NVH division at a car company cause I hear and feel EVERYTHING in my cars and can generally isolate and fix the problem. Sometimes I think it's almost a curse lol.

Next question, I got my air filter and cabin micro air filters from Joe (thanks Joe!) today. Is the process for the cabin filters basically the same as this: G35 removal & install . Thank you guys for the help!!

Post by **elwesso** » Tue Jul 13, 2004 5:59 am

Falk.. Im going to look it up in the parts book and see if I can find a PN for you...

Post by **Falkdesigns** » Tue Jul 13, 2004 5:59 am

thx Wes, what about the cabin filter replacement?

Post by **elwesso** » Tue Jul 13, 2004 5:59 am

I cant tell you about that, and Im having probelms finding that part...

I took a screen shot of the parts diagram and tell me if you can tell me what part it is... If they gave you a diagram tell me what section it is in...

Post by **Falkdesigns** » Tue Jul 13, 2004 5:59 am

Nothing there is it. I don't have the diagram they gave me, I've searched for pics on line, I think I'll take a pic of it when I get home.

Post by **Falkdesigns** » Tue Jul 13, 2004 5:59 am

K, here's pics of it. It's about actual size. So what's this called? We put the stethoscope on it and it's like hhweeeeeeeeeee sort of whisle, and I touched all over the place with the steth, and it's 100% coming from this piece.

Post by **elwesso** » Tue Jul 13, 2004 5:59 am

Kevin, I just spent an hour looking at every single diagram in the parts catalong and I am still not sure what this damn thing is...

From what I can tell with all my diagrams, this looks like the fuel pressure regulator.. its in the approx. spot that it should be in, and it even looks like the regulator, but its not.. There hsould be a hose going into it...

If I knew what the fast idle cam is called in nissan's terms that would really help...

Goddam Im as pissed as you are right now trying to figure out what this thing is......

Post by **Falkdesigns** » Tue Jul 13, 2004 5:59 am

Ha! mystery part. Where's Q45tech at? Well, I know that what it does is stops the throttle from closing all the way abruptly. When you let go of the throttle, the L bend on the throttle hits the plunger (where the nut is on the end of the plunger) on the mystery part and then slowly closes. It's got no hose or power other than that vacuum hose and it's only held on with two phillips screws, you can see one in both pics.

BTW, thank for the help Wes!

Post by **maxnix** » Tue Jul 13, 2004 5:59 am

I posted the cabin air filter procedure some time back. Fairly straight forward, just start with the passenger's lower dash valence and get the reinforcement bar and the glove box out. The FSM has a good detail.

The filters are stacked.

Post by **3Q Jay** » Tue Jul 13, 2004 5:59 am

try 'dashpot' at least that's what they were called on the old carburated beasts of 30 years ago.falk has described it's operation quite well. no relation to fuel lines.another genric term might be vacuum solenoid.

Post by **3Q Jay** » Tue Jul 13, 2004 5:59 am

and on the cabin filter, it's waaaayy easier than on the G35, and I own both.I didnt think the fsm was all that helpful, but Brian is right it is easy. just pull forward and slightly down, might have to disconnect the courtesy lamp. 4 screws on the glove box if i remember right and then the filter box is right there in front of you.

Post by **Falkdesigns** » Tue Jul 13, 2004 5:59 am

Thanks guys! Now if I can just get the name of that part! I told the dealer the number that's stamped on the part, but that didn't help...

Post by **elwesso** » Tue Jul 13, 2004 5:59 am

Could you give me that and I could try a reverse lookup?

Post by **Q451990** » Tue Jul 13, 2004 5:59 am

Why not just call Joe? He's the expert on looking these things up. It looks like replacement would be super-easy DIY (saves labor costs so you can buy tires)!

This looks like a mechanical replacement for having the IAC adjust for abrupt throttle closings...

Heath

Post by **Falkdesigns** » Tue Jul 13, 2004 5:59 am

That's a good idea. He's a cool guy, I got some stuff from him last week. Far as DIY, yeah, that would be a breeze to replace and I've always been a DIY guy with my cars, worked as a mechanic etc. Anyhow, thanks for the tip, don't know why I didn't think of that!

Post by **Falkdesigns** » Tue Jul 13, 2004 5:59 am

No one know's what that part's called? HEEELLLPP!! thx...

Post by **maxnix** » Tue Jul 13, 2004 5:59 am

I think it is the throttle opener, on FE-4 in the 2k FSM. It has a vacuum line going to it.

Post by **Falkdesigns** » Tue Jul 13, 2004 5:59 am

I don't think so, it stops the throttle from closing abruptly. Good try though! I called Joe yesterday, but he was out and I talked to another guy there, he said he'd find out and post up, he saw it while I was on the phone, but he never replied. I'll try to get ahold of Joe again today.

Post by **Falkdesigns** » Tue Jul 13, 2004 5:59 am

Ok, Joe's on it now, he's gonna order some stuff in to see if he can figure it out. Just spent about 20 minutes on the phone with him, can't believe what a challenge it's been to name this thing! LOL!! Thanks everyone for the help, suggestions, etc..

Idle air control valve question

Idle air control valve and micro filter questionPICS ADDED

Nissan Forums

Infiniti Forums

Datsun Forums

Technical Forums

Classifieds / Marketplace

Nissan Motorsports

General Forums

Idle air control valve question

Idle air control valve *and micro filter question*PICS ADDED

Nissan Forums

Infiniti Forums

Datsun Forums

Technical Forums

Classifieds / Marketplace

Nissan Motorsports

General Forums

Idle air control valve and micro filter questionPICS ADDED