I was driving home from work, and I noticed when I accelerate I hear a Hissing sound I've never heard before, I let go of the throttle and it stops

I checked under the hood and played a bit with the acceleration spring and it seems to me the hissing is coming from the intake manifold ... But I dont hear it that well standing over the block. Inside the cabin you can hear it a bit better..

:?

Just got a new flex pipe installed at the muffler shop... if it matters

anyone that has any ideas drop a line or 2 tongue.gif

 

I'm going to sound like a broken record here but.......

Has it been difficult to start your car in cold weather?? The only hissing sound that I have ever had was when I warped my IM. It got really cold out and I couldn't start my car. 02.gif

Basically the engine is sucking in air after the MAF and stalling out.

 

not hard to start at all

 

Is it running slightly slower? Sounds like a vacuum leak. Start the car, and spray starter fluid on different parts of the IM. If the idle changes, you have a leak.

 

I know that my Idle cotroller makes sounds like a king cobra when it is cold. It gets amplified by the aluminum intake piping. Try unplugging it and see if it stops. laugh.gif

 

It might be an air leak. Check your hoses around the sound. If you spray glass cleaner on the suspected hose, the engine will surge a little if there's a leak.

 

confused 8O

 

LOL...I guess if your starting a BBQ on your engine you can use the starter fluid...hell, maybe it works.. lol.gif

Seriously, I've never heard of starter fluid being done before (no offense hamhead, I'm just playing around)...I'll leave up to you tank which one you should use.

 

actually.. it sounds like an exhaust leak. The tip off is the fact that when he gets off the throttle, it stops. I would say the flex joint is not tight or the manifold to cat connection is loose. When on the throttle, the engine and tranny "twist" slightly.. this is why you have a flex joint, so you do not break the exhaust system when they happens. Because this is only happening when the engine is "twisting" in the car, it means that a joint in the exhaust is loose and is being pulled apart by the engine's movement.

 

okay i found my problem.. I have a crack in one of my header pipes

:x and I just replaced them 7 months ago..