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

Vacuum Leak

Thread Tools
 
Search this Thread
 
Old Feb 10, 2018 | 01:12 AM
  #1  
71CamZ's Avatar
71CamZ
Thread Starter
7th Gear
 
Joined: Feb 2018
Posts: 7
Likes: 0
Default Vacuum Leak

I'm new to the Corvette world and keep hearing how important vacuum leaks are, the problem I have is when I shut off the car I hear a hissing sound under the plenum, I tore apart the plenum and found the EGR Solenoid didn't have vacuum hoses on some of the ports. I figured they got rid of some of the EGR and didn't plug the ports. I bought some caps and covered them but still hear the noise. Can any one offer me advice? I have the car torn down now because im replacing the water pump.
Thanks
Reply
Old Feb 10, 2018 | 09:31 AM
  #2  
VikingTrad3r's Avatar
VikingTrad3r
Oil Producer
Supporting Gold
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Apr 2014
Posts: 9,363
Likes: 2,734
Default year

year please
Reply
Old Feb 10, 2018 | 10:58 PM
  #3  
71CamZ's Avatar
71CamZ
Thread Starter
7th Gear
 
Joined: Feb 2018
Posts: 7
Likes: 0
Default

Originally Posted by vikingtrad3r
year please
1986
Reply
Old Feb 11, 2018 | 08:57 AM
  #4  
corvette95's Avatar
corvette95
Melting Slicks
25 Year Member
Liked
Loved
Community Favorite
 
Joined: Jul 1999
Posts: 3,214
Likes: 101
From: Decatur, Alabama
Default

vacuum= bad+ check engine light. Could it be brake booster or cruise control?
Reply
Old Feb 12, 2018 | 07:56 AM
  #5  
playsdixie's Avatar
playsdixie
Drifting
 
Joined: Jun 2013
Posts: 1,590
Likes: 60
From: ft myers FL/Munising MI
Default

when you say "some of the egr stuff, is the valve still there or did they replace it with a plate?...if the valve is still there, it probably needs to be hooked to vac......easy way to look for vac leaks is to spray throttle body cleaner up and down the lines at idle... it'll increase if you spray one....if your car is stock, get a fsm......
Reply
Old Feb 13, 2018 | 09:55 PM
  #6  
71CamZ's Avatar
71CamZ
Thread Starter
7th Gear
 
Joined: Feb 2018
Posts: 7
Likes: 0
Default

Originally Posted by playsdixie
when you say "some of the egr stuff, is the valve still there or did they replace it with a plate?...if the valve is still there, it probably needs to be hooked to vac......easy way to look for vac leaks is to spray throttle body cleaner up and down the lines at idle... it'll increase if you spray one....if your car is stock, get a fsm......
The EGR valve is still there, your right it probably does need to be connected back where everything goes. Thank You!
Reply

Get notified of new replies

To Vacuum Leak





All times are GMT -4. The time now is 01:11 AM.

story-0
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

Slideshow: From C1 to C8 we compare every Corvette generation by the numbers.

By Joe Kucinski | 2026-05-12 16:54:12


VIEW MORE
story-1
8 Coolest Corvette Pace Cars (and Replicas) of All Time

Slideshow: Some Corvette pace cars became collectible legends, while others perfectly captured the look and attitude of their era.

By Verdad Gallardo | 2026-05-11 09:50:51


VIEW MORE
story-2
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

Slideshow: Ranking the top 10 Corvette engines by torque output.

By Joe Kucinski | 2026-05-05 11:58:09


VIEW MORE
story-3
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

Slideshow: A Corvette pace car nearly matching IndyCar speeds sounds exaggerated, until you look at the numbers.

By Verdad Gallardo | 2026-05-04 20:03:36


VIEW MORE
story-4
Top 10 Corvettes Coming to Mecum Indy 2026!

Among a rather large group of them.

By Brett Foote | 2026-05-04 13:56:44


VIEW MORE
story-5
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

Slideshow: the top 10 things Corvette owners want in the C9 Corvette

By Michael S. Palmer | 2026-04-30 12:41:15


VIEW MORE
story-6
10 Revolutionary 'Corvette Firsts' Most People Don't Know

Slideshow: 10 Important Corvette 'firsts' that every fan should know.

By Joe Kucinski | 2026-04-29 17:02:16


VIEW MORE
story-7
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

Slideshow: Should you buy a 2020-2026 Corvette or wait for 2027?

By Michael S. Palmer | 2026-04-22 10:08:58


VIEW MORE
story-8
2027 Corvette vs The World: Every C8 vs Its Closest Competitor

Slideshow: 2027 Corvette lineup vs the world.

By Joe Kucinski | 2026-04-24 16:12:42


VIEW MORE
story-9
10 Most Common Corvette Problems of the Last 20 Years!

Slideshow: 10 major Corvette problems from the last 20 years.

By Joe Kucinski | 2026-04-14 16:37:05


VIEW MORE