Throttle Blip Hiss
 

So lately I've been noticing a quick hissing noise during throttle blip - first started noticing it when blipping for downshifts, but can induce it blipping the throttle from idle. I've seen the other threads that talk about a knock or pop during blip, and I definitely do not have that. It happens at a rapid blip of the throttle and just sounds like a very quick hiss, almost like you can hear the air induction. Noise won't happen in other kinds of driving, rolling on throttle, WOT, etc. No other odd noise otherwise.

Anybody else notice this?

You may consider plugging up the sound generator tube at the firewall and see if you still hear the "hiss".

My 71 year old ears can't hear "hiss" and a lot of other sounds anymore ..... so, I don't know if my car hisses or not ..:iono:


humfrz

It could be noise coming from the sound tube. Try covering it and replicating it.

You're 71!?

And a veteran too I believe. One that can use a computer quite well.

Yes, that's what he said!?

:lol:

No. His ears are 71.

Haven't tried plugging the sound tube, but it's audible from outside of the car and with the windows down.

Yep, if you saw me ....you'd believe it ..... :confused0068:



humfrz

I hear the hiss too...pretty sure its normal

Yep, Viet Nam era veteran.

Well, I had a head start with home computers, when I purchased my first one back in '82 for $99.95.

It was called a Timex Sinclair 1000 ...... and it was a screamer ....:D Used a cassette recorder for data storage and a B&W TV for a monitor.

Anyone still with me .. ?? Anyone .. ??

OK, time to go eat my oatmeal ..... :bonk:


humfrz

The hiss is definitely not normal. I had a similar sound occur about a month or two before the pilot bearing went out on my clutch (something I was told by a mechanic is quite common on Subarus). So, if you're hearing a sound like you've got a vacuum leak or hiss when you blip the throttle, it may be a sign that the clutch pilot bearing is about to go soon. Hissing will go away and come back intermittently. Then there will be a rattle when it does go.

Keep an eye on this and don't just write it off as normal noise. If it isn't something you expect to hear, then it is never normal noise. Hopefully yours is not as severe an issue.

I hear a clicking that's rather mechanical, I've always attributed it to the electronic throttle quickly snapping open the throttle valve when I stab the gas.

:iono:

Video? I don't hear any "hiss". But my quiet may be your hiss, who knows...