C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine

Hissing noise under dash (92)

Thread Tools
 
Search this Thread
 
Old 03-27-2004, 09:52 AM
  #1  
jimswhite92
Racer
Thread Starter
 
jimswhite92's Avatar
 
Member Since: Jan 2003
Location: Birmingham AL
Posts: 321
Likes: 0
Received 0 Likes on 0 Posts
Default Hissing noise under dash (92)

along with a hard brake pedal. After searching the archives it appears my brake vacuum booster is shot. Sounds like it's a PITA to replace.

What brand are you guys replacing the booster with. Do you recommed a factory replacement or will the NAPA, Auto Zone parts be OK???

Thanks ... Jim
Old 03-27-2004, 09:59 AM
  #2  
Nathan Plemons
Race Director
 
Nathan Plemons's Avatar
 
Member Since: May 2001
Posts: 14,165
Likes: 0
Received 9 Likes on 8 Posts

Default Re: Hissing noise under dash (jimswhite92)

Well I haven't had to replace mine but it doesn't seem like it would be THAT hard. All you should need is a tripple jointed spine.

You said you've searched the archives, so you've probably already checked all the obvious. There are several vacuum lines around the pedals, have you double checked them just in case. It would really suck to replace the booster over a cracked line.
Old 03-27-2004, 10:02 AM
  #3  
jimswhite92
Racer
Thread Starter
 
jimswhite92's Avatar
 
Member Since: Jan 2003
Location: Birmingham AL
Posts: 321
Likes: 0
Received 0 Likes on 0 Posts
Default Re: Hissing noise under dash (Nathan Plemons)

Only hear the noise when I apply brake and after searching the archives I made an assumption.

I'll be checking the vacuum lines before I do anything.

Thanks
Old 03-27-2004, 10:09 AM
  #4  
Nathan Plemons
Race Director
 
Nathan Plemons's Avatar
 
Member Since: May 2001
Posts: 14,165
Likes: 0
Received 9 Likes on 8 Posts

Default Re: Hissing noise under dash (jimswhite92)

Either the clutch or the brake pedal, possibly both, have vacuum switches that are used to cut the cruise control. If one of those popped off it MIGHT cause your trouble. I'd say you're probably right about the booster but it never hurts to check. I know how hard it is to get under that dash and I'd hate to see anybody spend more time under there than needed.
Old 03-27-2004, 12:18 PM
  #5  
86PACER
Le Mans Master
 
86PACER's Avatar
 
Member Since: Jan 2003
Location: Santa Maria CA
Posts: 5,858
Likes: 0
Received 5 Likes on 5 Posts

Default Re: Hissing noise under dash (jimswhite92)

Those are classic symptoms of a bad brake booster. I had the excact symptoms you describe. There are replacements. They come in plastic like the original, and also come made of metal. The metal ones are a good choice if you want to be sure the drivers header wont melt a hole in it by heat. I got a metal one for less that $100 at a local Advace Auto Parts. Some come with a lifetime warranty. They are easy to replace. The hardest thing will be getting to the bolts holding it to the firewall from under the driver's dash. A ratchet with an extension and a u-joint will work nicely. If your tall, laying down under the dash will be the harderst part. Overall, it's cake. Definatly not a P.I.T.A. Just be sure not to drop the mouting bolts behind the carpet. Good luck. :thumbs:




[Modified by 86PACER, 9:27 AM 3/27/2004]
Old 03-27-2004, 06:37 PM
  #6  
jimswhite92
Racer
Thread Starter
 
jimswhite92's Avatar
 
Member Since: Jan 2003
Location: Birmingham AL
Posts: 321
Likes: 0
Received 0 Likes on 0 Posts
Default Re: Hissing noise under dash (86PACER)

It looks and sounds doable. I'll find the parts and tackle it soon.

Thanks for the help ... Jim

Get notified of new replies

To Hissing noise under dash (92)




Quick Reply: Hissing noise under dash (92)



All times are GMT -4. The time now is 04:27 AM.