I have been noticing what sounds like an hissing / swirling air noise while accelrating around 1800RPM or so. Anything below that or about 2000RPM and nothing.

Anyone else expirence this or know what it may be? I've already checked the exterior connections to the intake.

Vehicle is 100% stock, no mods.
Thanks!

I have been noticing what sounds like an hissing / swirling air noise while accelrating around 1800RPM or so. Anything below that or about 2000RPM and nothing.

Anyone else expirence this or know what it may be? I've already checked the exterior connections to the intake.

Vehicle is 100% stock, no mods.
Thanks!

Nope, never heard anything like it with a stock airbox. If you feel like checking, pop the hood and make sure all connections are tight at the airbox and to the engine. If all is snug, take it to the dealer.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by H2 007:
I have been noticing what sounds like an hissing / swirling air noise while accelrating around 1800RPM or so. Anything below that or about 2000RPM and nothing.

Anyone else expirence this or know what it may be? I've already checked the exterior connections to the intake.

Vehicle is 100% stock, no mods.
Thanks! </div></BLOCKQUOTE>

Don't know what it is as I'm trying to figure it out myself. Mine happens in the specific RPM band you described, though I am pretty sure it's not anything from the airbox to the intake, this happens with either my stock setup or the Airaid JR kit. Mine is 05 as well.

I was listening to it again today on the way home and it almost sounds like a whistle noise.

I don't really want to take it into the dealer as I'm getting like 13MPG around town and 16MPG on mixed highway driving.

It drives fine, so I'm kinda thinking leave it alone, but would like to know what's causing it.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by H2 007:
I was listening to it again today on the way home and it almost sounds like a whistle noise.

I don't really want to take it into the dealer as I'm getting like 13MPG around town and 16MPG on mixed highway driving.

It drives fine, so I'm kinda thinking leave it alone, but would like to know what's causing it.

</div></BLOCKQUOTE>
You might want to go ahead & take it in as soon as possible. They're going to need to replace that defective computer before it affects other vehicle operations. 16 mpg, LOL I wish. The only way I can see an H2 getting over 14 mpg in "mixed" driving is on perfectly level ground while you mix it between 40 & 45 mph, with a strong tailwind, while drafting an 18-Wheeler, with the A/C off of course.

No kidding on the mileage. I have a real light foot these days and couldn't be happier with the mileage I'm getting from the H2. It's actually about 3 MPG better than I was getting with my F250 with the 5.4L gas engine.

I've got about 1500 miles on it now and the worst I've gotten has been 12.1MPG. This is all hand calculated also.

Had mine for exactly one year today. 10.9 for the year. Mixed driving. Would give up a kidney to get 14-16.

Drive with the a/c off, never idle for extended periods, drive no more than 15% throttle and limit your speed to 45 mph, and you just might get your wish.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Hummertech:
Drive with the a/c off, never idle for extended periods, drive no more than 15% throttle and limit your speed to 45 mph, and you just might get your wish. </div></BLOCKQUOTE>

Now, any idea on the "sound"?

Vacuum leak. Check the lines.

Checked already Ken, besides, if it were vacuum, it should be making constant sound rather than what was described.

Thanks.

got my '05 H2 just a couple of weeks ago. I too noticed this noise. Dealer says it is most likely a valve on the air intake that makes this whistling sound - apparently normal. I'm going to have them take a closer look at it.

Greenhummer

I've noticed that it only seems to do it while in 2 or 3rd gear, again only between 1500 and 2000 RPM.

Then again it doesn't do it all the time. I'm wondering if more people have this and just haven't noticed it. It's hard to hear if you have the windows up, much less the radio or the air on.

Doesn't seem to be causing any problems either.

When stock I never had it on My 2005 H2. Now with all the upgrades all I hear is a big tornado sucking air.

It can be vacuum related as some vacumm lines are hooked up to where rpm's can change how much vacumm it has. Like on a boost gauge uses vacumm in the intake manifold and My Keene Bell boost a pump uses vacum as well. It allows increased fuel pressure by adjusting the vacumm switch. Not directly pulling more fuel but, how it reads pressure and increase the electrical output like a reostat.
It could be a vacum line doing it. KenP is correct. I never had it so I wish I could be more help.

TAZ