As the title states, theres a hiss comming from my car.
-When the key is off, there is no noise.
-When the key is in acc no noise.
-When the key is in on position, no noise
-when the car is running, there is a hissing sound noise comming from around the rear axel.
Based on what has been said, its not my tires or shocks. I have also heard that your fuel pump continues to run for 5 secs AFTER your car has been turned off. Is this True?? because if it is, my fuel pump is out of the question because the noise stops the second the car is off. I THINK I have noticed my car going through the gas rather fast..... I am going to raise it on a hoist today and look underneath.... Any Ideas????

 

Is it from the driver or passenger side? You might have a leak near the evap purge valve or charcoal canister.. both are under the rear bumper, driver's side of the car.

 

Either that, or you have the Cobra edition. :wall"

I know, its a pathetic joke, but I'm just trying to get through the day

 

Id say the noise is more near the gas tank/ axle....

 

Does the noise happen right after a cold start? It could be a bad gas cap... that is letting the fuel fumes/vapors seep out... I had this problem on my previous car.

 

I've never heard a fuel pump running 5 sec after being turned off. I say fuel pump. I can't really see EVAP having enough pressure to hiss all the time like that (and only when on). Not to mention, if it were an evap fault, you'd most likely have a CEL. The ECU does monitor EVAP function.

Trav

 

Good point on the EVAP CEL.

 

There is no CEL on. The noise starts Instantly. The second I turn the car on, It does not matter if the engine is hot ot cold. I THINK (hard to tell) the noise increases , if I increase the throttle. (gas petal).
I Will check the gas cap after work here, because I did fill the tank, then noticed the problem later that night.

 

possible exhaust leak?

 

its ur evan canister and valve. the same this is wrong with my I30. i just live with it and the CEL cause i have better things to spend my money on lol

 

I have the same problem now, an 01-11 code just randomly popped up on my car and I have no idea whats wrong. From what I have read, the EVAP system is jhust another emissions controll system right? So driving with one that has a problem wont cause any other problems right?

 

thats the most obvious exhaust leak problem i've ever heard...

but i can be wrong.

 

exhaust leak isnt going to throw a CEL.

 

yeah but my car hisses too and no CEL.

 

haha, oops, I am confusing two different threads, I thought the original poster said he had a CEL. nm.



edit: when you have an exhaust leak, your exhaust usually gets louder, it wont just start hissing. if you ever bolt on a new cat or something and dont use gaskets, youll see what I mean.