Air hiss coming from engine

2013 Geee T

Founding Member

Sep 25, 2002

805

5

19

Oak Park, CA

Nov 7, 2007

#1

• Nov 7, 2007

• #1

I'm starting to notice an air hissing sound coming from my engine when I start it in the morning. I can even hear it from inside the car. It sounds like its coming from around the plenum/throttle body area but I haven't tried to pinpoint it yet. If I give it gas it affects the sound. I'm pretty sure once it warms up it either goes away or is not as loud. It seems to be louder when its colder. Any ideas?

 

timeless2

Vi Veri Veni Versum Vicus Vici

Admin Dude

Nov 29, 1999

1,366

202

154

the Shadow Gallery

Nov 7, 2007

#2

• Nov 7, 2007

• #2

Any vacuum hoses disconnected? Check for punctures as well. As rubber heats up, it swells and could partially seal up the fissure. When it's cold, the gap is wider due to contraction of the material ==> louder sound.

 

2013 Geee T

Founding Member

Sep 25, 2002

805

5

19

Oak Park, CA

Nov 7, 2007

#3

• Nov 7, 2007

• #3

Thats what I was thinking. Ill have to get in there and dig a little deeper. It seemed to have started shortly after doing the plugs so maybe something got bumped loose.

 

S

SilverBullet00

New Member

Jul 5, 2004

1,150

0

0

Wichita, KS

Nov 7, 2007

#4

• Nov 7, 2007

• #4

Mine has done that since I bought it. I have never been able to find the source

let us know if you find anything!

 

RandyStinchcomb

New Member

May 25, 2005

1,159

3

0

Randallstown, Md

Nov 8, 2007

#5

• Nov 8, 2007

• #5

another common problem: check the PCV hose going from the PCV valve to the plenum, very common problem lately on 2002 to 2004 Gt's

 

2013 Geee T

Founding Member

Sep 25, 2002

805

5

19

Oak Park, CA

Nov 8, 2007

#6

• Nov 8, 2007

• #6

Where exactly is the PCV valve on these cars? I looked for it but couldnt find it unless its hidden or looks like something else.

 

RandyStinchcomb

New Member

May 25, 2005

1,159

3

0

Randallstown, Md

Nov 8, 2007

#7

• Nov 8, 2007

• #7

2003 Geee T said:

Where exactly is the PCV valve on these cars? I looked for it but couldnt find it unless its hidden or looks like something else.

Click to expand...

middle of the rightside cam cover

 

2013 Geee T

Founding Member

Sep 25, 2002

805

5

19

Oak Park, CA

Nov 9, 2007

#8

• Nov 9, 2007

• #8

As in passenger side?

 

RandyStinchcomb

New Member

May 25, 2005

1,159

3

0

Randallstown, Md

Nov 9, 2007

#9

• Nov 9, 2007

• #9

2003 Geee T said:

As in passenger side?

Click to expand...

correct passenger side = right side..........driver side = left side

 

Mike97gt

it doe snot

Founding Member

Jan 26, 1999

10,633

7

89

the people's republic of massachusetts

Nov 9, 2007

#10

• Nov 9, 2007

• #10

If it is not the PCV hose or any other hose check the PCV valve itself. If that don't fix it try this.

WHILE IT"S MAKING THE NOISE

While holding the TB slightly open and unplug the IAC if the noise goes away then it is the IAC valve. they nornally don't make a hissing noise they make this strange air vibration noise I really can not describe

 

2013 Geee T

Founding Member

Sep 25, 2002

805

5

19

Oak Park, CA

Nov 9, 2007

#11

• Nov 9, 2007

• #11

I replaced the IAC valve about 4 months ago but Ill check it out.

 

2013 Geee T

Founding Member

Sep 25, 2002

805

5

19

Oak Park, CA

Nov 13, 2007

#12

• Nov 13, 2007

• #12

All I see on the cam cover in the middle is a hose with an electrical connection attached to whatever its plugged into. Its right under the air intake tube. Is that it?

 

blckstng96

Member

Apr 13, 2004

208

0

16

Nov 14, 2007

#13

• Nov 14, 2007

• #13

take a can of carb cleaner and while the car is running spray it around hoses and the unpper intake and stuff.do this all one thing at a time.if the idle changes you have found your leak.mine did the same thing.happened to be the unpper intake manifold.on the under side of it where it meets the throttlebody there was some sort of factory plug.that plug worked its way outon its own.try that