westpak

iTrader: (19)

He probably means that the car will act like it is going to die because it is trying to run with the wD40 in the fuel/air mix, you will not get bubbles as it is sucking in air not blowing air.

SungNamZ

Chris, definately sounds like you have an air leak somewhere. I am still waiting for my Plenum that PriceWise says was shipped, 3/1/2004 however FedEx says label was printed however they have not taken possission of the Plenum/Cats. so can't speak from Plenum experience.

However, had similar problem last week. Car would idle at 750 and then drop to approximately 600. Drove me crazy for about two weeks. Car while driving seemed fine. Discovered the hose fitting on the bottom of the tube was broken. Replaced with "new" tube and the problem went away immediately.

ChrisMCagle

Hmmmm.. which hose do you mean? I know that I had to take hoses on and off a bunch of times during the install process because I would forget to take pictures and things. It's possible that there is a loose or damaged hose, but I'm going to try the WD40 test first.

So what happens if I spray WD40 all around the plenum and there is no difference and the car still runs like it currently is? Does that mean that I am in the clear as far as a leak? I don't really think that I have one though because the car runs fine while driving. Wouldn't it run liks $hit if there was a leak??

-Chrismcagle

zxsaint

In the past i've done this using a carb/throttle body cleaner spray.

Spraying WD40 seems like it'd make a nasty oily mess around the plenum. Is it even safe for the engine?

SungNamZ

For me, it was the hose on the bottom of the intake tube. It was completely removed. No noticeable difference while running, but at idle, did exactly what you describe. Check everything from your OEM Air Intake all the way to your Throttle Body.

all_bark

iTrader: (5)

I agree that you have a leak.

dont only check the outside bolts but also check the two bolts on top of the plenum where they screw down into the interior posts. that could also be the problem. FYI - a big leak will stall the car while a little leak will make the idle jump and not stay in one place.

btw-i do not have the same problem, my idle is perfecto!

StrictlyZ

Chris,

Yes I guess you can use carb cleaner or brake cleaner, but its more combustible then WD40. ZXsaint is right it will make your engine bay messy.

All i'm trying to say is that if you spray and it stumbles that means you have a leak coming from that area. If you have a small leak you should feel it in higher rpm. Its just when your sitting at idle.

This is just from my experience. Heh I knew i was going to get hit for the WD40

ChrisMCagle

Well... Shhhhhhhhoooooooooooot! I REALLY do not want to take the plenum completely off. I cranked down those 4 bolts that attach to the top of the interior plenum really well so I am positive that those are not the problem. On my way home I took the street so that I would stop frequently at red lights so that I could see what the idle did. I was so bored that I actually kept track of the number of lights and how the idle behaved at them:

There were a total of 19 intersections of which I had to stop at 12 (lucky me, huh?).

Of those 12 stops the average duration was about a minute.

Out of the 12 times stopped, the idle stayed at a constant rpm (usually around 740 to 750 rpms) 9 times.

It only dropped to around 600 rpms 3 times.


Does that mean anything?

I notice that when the car is cold, the idle seems to fluctuate more than when the car is hot, if that matters.

-Chrismcagle

ChrisMCagle

Hey all_bark,

Are you going to be in the Orange County area anytime soon? <wink wink>

-Chrismcagle

zxsaint

Just installed mine tonight ... I think I have a leak tho. Heard a loud whistle for a few seconds while driving it.

So how about the gurgling/growling sounds... is this a characteristic of the plenum?

ChrisMCagle

Yes, you most definitely have a leak if you heard any type of "whistle".

Mine definitely has a more "growling" sound to it. Not sure about the gurgling though. I don't think mine makes any noises like that, although it could just be that what sounds like one thing to me (growling) sound like something else to you (growling/gurgling). I am sure that you do have a leak though because of the whistle. Just tighten the perimeter screws a little more as well as the 2 on the top and the 4 on the throttle body. Did you leave the stock gasket in place?

-Chrismcagle

lsdunique

iTrader: (3)

At idle, the plenum makes a type of growling sound.

We always check air leaks with a spray bottle of water with a little soap mized in.

Be sure that the flange bolts are being torqued at 36 inch/lb and that the threadlock is used. Also I advise waiting a good 30 minutes before starting the car after installation so the threadlock can set.

zxsaint

I left the stock gasket in place, but I removed the one on the throttle body since I had a hard time getting the hex screws for that to go in right.

My kit came with some hardware I didn't end up using. Two black bolts and two 1/2" white plastic washers. Not sure what they were for.

Also, the hole next to the throttle body (the one you had to drill) .. I can't get anything to fit in there. What bolt did you use? The only thing that catches is one of the long dark oem bolts from the original plenum, but it doesnt go in all the way (keeps spinning w/ reisistance)

all_bark

iTrader: (5)

one the long bolts that go into the factory plenum are to be used for that hole. there are long ones and ones that are even a bit longer. try the longer of the two. if it does not line up, loosen all of the bolts and giggle the plenum around until it hits and starts to screw in. you should also put the original throttle body gasket back on. i did it when the plenum was off the car!

zxsaint

I drove this car to work this morning and had no problems (no whistle). Just the resonating growl which seems just characteristic of the plenum. Seems like the threadlock may have needed to set in.

JST4FN

Is the growl annoying? I'm looking at doing the plenum and high flow cats before the sale runs, but I want stock behavior or close to it as far as noise is concerned.
Thanks Mike

zxsaint

It's definitely not annoying. It's not too loud at all and the tone just adds more character to the engine's aggressive sound.

I drove her again and she was a lot smoother. Solid idle, feels great. Giving it time to settle/break-in makes a big difference.

all_bark & chris... do you guys have a hissing sound at idle coming from the lower left area below the plenum? I don't remember if the oem setup had this. It seems to be coming from the bottom left area facing the front of the car (near the hose). I sprayed this and every other edge heavily with carb cleaner and had no reaction so I'm pretty sure it isn't a leak -- but was just wondering what this hiss could be.

As far as the throttle body gasket, I really feel like it's got a good seal. I doubled up on the washers for the hex bolts since they didn't really wanna go in all the way, but I can see the cork gasket is squeezed evenly for a nice tight seal around it. As far as the bolt at the top, I'm considering not even using it. It seems like it's running great with no leaks and I dont really wanna fuss it with it unless I have a problem.

ChrisMCagle

zxsaint,

Yes, I do have the hiss as well but it was most definitely there with the stock plenum. I actually noticed it a couple weeks ago when I installed the UR pulleys so I know it was normal. If I hadn't noticed before, I would have been a bit concerned.

I also agree that the sound just adds some character to the car. It's not annoying at all... just a nice growl.

As for your "solid idle", is it solid at all times, like as soon as you start your car, or is it solid after driving it around for a bit?

Just curious.

Oh Yeah, one more thing. Those 2 white spacers and 2 black hex head bolts are used to mount the rear 2 points of the engine cover. I added that to the instructions a couple days ago. Unfortunately that the only way you will be able to get the right rear bolt in is if the strut bar is not on. I decided not to mount anything to those 2 holes and just have th eengine cover held in place with the 2 front bolts. It's VERY secure.

I'll add these torque specifications to the instruction site as soon as I get home today.

-Chrismcagle

zxsaint

I'll check the idle's behavior on cold startup in a few hours before my drive home.

Thanks for clearing up confusion about the white spacers and the hiss. I'm gonna go home and put the cover and strut bar back on and stare at this awesome setup for a while. I'll take a pic for all to see.

Torque specs will really help.. I did crack one mounting point, but no functional harm was done.

ChrisMCagle

No Problem. I am continually updating the instruction site (almost daily I change a bit here and there) so that it will clearly help those who install the plenum. That's why I made it

If you did crack the plenum anywhere, make sure that you repair it with some epoxy or something. A small crack now can turn into a big crack later.

-Chrismcagle