Weird humming from engine after Injen CAI install

[Albert]

Ok, I just got my CAI installed a little over a week ago. Since then, I sometimes get a humming sound coming from my engine at between 3-4K RPM's (mostly between 3.5 - 4K). It goes like this:
1. Accelerate.
2. Hear the whooshing from the CAI sucking in air.
3. Hear turbo start to whistle.
4. Hear the hummmmmm for less than a second.
5. Keep accelerating like normal.

The best way to describe it is it's like when you drive on the rumble strips on the side of the expressway, but a lot more subtle. Here's what I know: It happens in every gear, it happens only under moderate to hard acceleration, it lasts less than a second, it doesn't affect the car at all as far as I can tell.

My questions are: Does this happen to anyone else? Could it have been there all along and I only hear it now because everything's louder with the CAI? and most importantly Does anyone have any ideas on what it is I'm hearing? Like I said, it doesn't seem to be affecting the driveability of the car at all, but I hope it's not ******* something up!

Thanks.

 

[changedman]

its prolly just louder with the cai. check the install again, make sure everything is tight and properly connected.

 

[Albert]

I went over the installation and everything seems right and nice and tight. I even tried to press the CAI up against the sides of the hole it goes into to see if it was some weird vibration, but I installed it tight and it doesn't hit the edge of the hole.

Could it just be another noise made by the BOV?

 

[hesitationhater]

Ok, I just got my CAI installed a little over a week ago. Since then, I sometimes get a humming sound coming from my engine at between 3-4K RPM's (mostly between 3.5 - 4K). It goes like this:
1. Accelerate.
2. Hear the whooshing from the CAI sucking in air.
3. Hear turbo start to whistle.
4. Hear the hummmmmm for less than a second.
5. Keep accelerating like normal.



Thanks.

Do you have a boost gauge? What you describe sounds exactly like mine, and there is a huge drop in boost when it makes that sound.

You don't feel anything at all? Everyone who has rode with me this week can tell when it drops from 6.2 down to like 4 when the car should just go.

 

[GI-]

I believe I have the same issue with mine. At first I thought that maybe the filter had slid up the intake tubing in the wheel well under hard acceleration, when there was alot of initial vacuum, but this wasn't the case. Everything is installed as it should be. I believe it is the stumble/hesitation just being amplified through the cold air intake!

 

[Dexter]

i havent particualily noticed this issue, but i will pay attention today for it

 

[Albert]

Do you have a boost gauge?

No, not yet. Getting one before I install Joe's MBC, tho.

Maybe my butt dyno is broken, because I don't notice any difference. LOL

 

[MoJoeTCM]

Why does everyone call it the BOV!!! IT IS A BYPASS VALVE! The rubber thing you know? That runs from the Stock air intake to the intercooler piping! Anyway, did you get any performance gains from the CAI?

 

[Albert]

****** semantics ...

Why does everyone call it the BOV!!! IT IS A BYPASS VALVE!

My humblest apologies.

Will it help to say that I meant to type "BPV" and mistyped it?

you know what I ****** meant ...

Anyway, did you get any performance gains from the CAI?

Yeah, it makes a sweet humming noise - good for 15WHP at least!

 

[MoJoeTCM]

It is cool, but curious...When you take off the stock you obviously loose the hp it originally has, so how much does it add with that few taken away? Was that a guess or a definate...Is it noticably quicker!?

 

[Albert]

Actually the 15 WHP from the humming noise was meant as sarcasm ...

As far as increases, I can't really tell you. I've been driving around with 140 lbs. of sand in my trunk because my Spool springs are f'ed up (there's another thread about that, and it's being taken care of by a very cool Terry), so my car isn't rarin' to go like it should be. There's been many threads about the CAI, and some of them even posted before and after dyno's. Search for it, but be warned, you'll have to search thru a lot of crap before you get to the real info.

At least it sounds faster now.

 

[KyRaceFan]

could this be a wastegate issue letting off excess boost? with the addition of a CAI, the car might be making a little more boost than the wastegate is set to handle, and could just be bleeding it off a little once you reach full boost.

And, without a freer flowing exhaust, i doubt your getting 15whp from just a CAI, now however, if you couple that with an exhaust, youre going to gain a big difference

 

[boostisgood]

could this be a wastegate issue letting off excess boost? with the addition of a CAI, the car might be making a little more boost than the wastegate is set to handle, and could just be bleeding it off a little once you reach full boost.

And, without a freer flowing exhaust, i doubt your getting 15whp from just a CAI, now however, if you couple that with an exhaust, youre going to gain a big difference

First, a CAI will not increase boost. It will increase volumetric efficiency.

A wastegate opens when you acheve the preset boost. The Wastegate lets the excese Exhaust gas out, before the turbo, to avoid more boost being created.

And YES you can gain 15 WHP from a CAI on a boosted car. Its all about the volume/density of air, and a CAI gives the MSP that.

 

[Albert]

urgh ... read people. READ

I said it once, and here it is again ...

THE 15 WHP WAS A JOKE! Sheesh. If you read it, it says that the weird humming is good for 15 WHP ... you guys are killing me!

 

[David MPS]

Re: urgh ... read people. READ

I said it once, and here it is again ...

THE 15 WHP WAS A JOKE! Sheesh. If you read it, it says that the weird humming is good for 15 WHP ... you guys are killing me!

I will surely test that with a g-tech pro. The "Before" and "After" I'm interrest about the diffrence not the quantities. I believe the 10whp minimum with a CAI, increase the Flow, the CFM will increase too.

 

[KyRaceFan]

i agree, a CAI can net you 15whp, but not on stock boost levels, and stock exhaust. Also please go reference the posts made about the k&n panel filter install. Some good info from some extremely knowledgeable friends of mine.
And since you are flowing more air, its possible that hes hitting the preset boost level, and the wastegate opens briefly to vent it.
Somone correct me if im wrong, but i thought waste gate wasnt on the hot side... that would be an emissions legality nightmare, and it would dirty your engine up quick

 

[Dexter]

nope, no humming.

 

[JDM Sam]

Hey GI I think I see ur woman's titty in ur avatar! (boobs)

 

[TampaBlackMSP]

Haven't noticed that at all with mine.

 

[HAIL-MY-SPEED]

I don't know if you guy's have seen this before. I'm at work and I am to lazy to do a seach!

http://www.speedoptions.com/articles/3425/?SpeedOptions=26aecc0f578c12849c21d38664073df2