Engine Hiss under load

[Hyperion]

Hey guys, so while under heavy load, (cannot make the sound while revving at a stand still)my engine makes a sort of a hiss. Hiss is a weird work to use, but I can't think of a better word.
i semi-recently had headers installed, so I'm wondering if maybe there's a leak on them, or could it be something else?

Edit, I also get a squeak when turning on the A/C, does something need to be tightened there too?

[Mitchell3]

I've had this too, but when I got the CAI put in it all kind of sounds the same lol. I haven't the faintest what it is but I know exactly what your talking about.

[Hyperion]

Probably not, I've been running stock air box for some time now :p

[Cab0oze]

A hissing noise is a good indicator of a leak although can't really offer any more advice than that... its possible that something isn't tight, and when the engine shifts when in gear it leaks a bit?

Squeak when turning on the AC... is that from outside the car? Might be the belt is slipping a bit or is wet.

[Hyperion]

The squeak you can hear from inside the car, and will happen at any random given time while driving and the ac s on

[JonsMazda]

The squeak you can hear from inside the car, and will happen at any random given time while driving and the ac s on

I believe its normal, i know what you're talking about...happens to my car as well.

[Hyperion]

I believe its normal, i know what you're talking about...happens to my car as well.

If the car doesn't come with it, it's not normal lol.

[thanu31]

spoolinggggg ;)

[Genpu_Mz3]

my ac squeeks to, i think it might be the a/c clutch kicking in, try some wd-40 that might work. as for the hiss, i think it would be a lil more obvious if it was a leak in your header. maybe your intake gets louder when the car is under load from trying to bring more air in? just an idea

[Jackal]

Just get an sri or cai and you won't hear these sounds due to the awesome sound of the intake.

[Chrisinski]

Doesnt it take a week or two for the new gasket around the headers to actually properly seal? Could have swore this was an issue on my friends civic and he was also getting CELs due to this and then about 2ish weeks later or so the sound went away, cleared computer and it was fine after that. I want to say this is the case. I think some homework on header issues after install would be a good thing EX: youtube.


Regardless you should have a SRI. Gives the vehicle a nice tone from the front.

[Hyperion]

I don't think you people know who you're giving advice to. As the owner of one of the most modified cars on this forum, I think I know what an intake would do. If I post with a question, is because I have not being able to think of a solution myself and I'm looking for others input towards fixing it.
Cab0oze, 2010, ty for the input.

[Mitchell3]

Probably not, I've been running stock air box for some time now :p

I had it when I was stock as well. It sounds like something releasing air pressure is how I would describe my noise before the intake drowned it out.

[Kiyomi]

is the rad cap on tight?