Forced Induction Superchargers | Turbochargers | Intercoolers

Problems with boost gauge HELP!

Old May 26, 2010 | 06:26 PM
  #1  
1998TA__1991RS's Avatar
Thread Starter
TECH Fanatic
iTrader: (23)
 
Joined: Nov 2004
Posts: 1,306
Likes: 0
Default Problems with boost gauge HELP!

I can not get my boost gauge to work, its an autometer 3404. the gauge is plumbed into the back of my intake elbowwith a brass fitting. if i crank the car up i have vaccum on the hose going to the gauge at idle, and if i blow into the back of the gauge it reeds boost. i cant think of another reason it wouldnt be reading any ideas? heres the gauge i have:

Reply
Old May 26, 2010 | 06:31 PM
  #2  
MadIceV8's Avatar
Customizing Director
20 Year Member
iTrader: (12)
 
Joined: Mar 2002
Posts: 5,778
Likes: 4
From: SW Chicago, IL
Default

Um... boosted cars pull vacuum at idle. It isn't until you are actually driving the car that you will see boost.
Reply
Old May 26, 2010 | 06:38 PM
  #3  
XtremeDime's Avatar
TECH Addict
iTrader: (16)
 
Joined: Jul 2005
Posts: 2,899
Likes: 0
From: Anchorage, ALASKA
Default

Lol..
Reply
Old May 26, 2010 | 07:38 PM
  #4  
1998TA__1991RS's Avatar
Thread Starter
TECH Fanatic
iTrader: (23)
 
Joined: Nov 2004
Posts: 1,306
Likes: 0
Default

Originally Posted by MadIceV8
Um... boosted cars pull vacuum at idle. It isn't until you are actually driving the car that you will see boost.

im not that stupid, lol, im saying if it pulls vaccum at idle it should obvioussly read boost under a load, ive foot braked the car under load and put it on the trans brake and it still doesnt read when a load is applied, nor when im going down the track
Reply
Old May 26, 2010 | 08:00 PM
  #5  
XtremeDime's Avatar
TECH Addict
iTrader: (16)
 
Joined: Jul 2005
Posts: 2,899
Likes: 0
From: Anchorage, ALASKA
Default

Is the hose getting kinked anywhere?
Reply
Old May 26, 2010 | 09:20 PM
  #6  
black98ws6ta's Avatar
TECH Addict
iTrader: (77)
 
Joined: May 2002
Posts: 2,107
Likes: 2
From: louisville,ky
Default

If you tighten down the compression fitting to much it can kink it closed?
Reply
Old May 26, 2010 | 11:10 PM
  #7  
MadIceV8's Avatar
Customizing Director
20 Year Member
iTrader: (12)
 
Joined: Mar 2002
Posts: 5,778
Likes: 4
From: SW Chicago, IL
Default

Did you hook it off of the vacuum hose that normally went to the air pump? As that hose has a little check valve in it that will prevent boost reading.
Reply
Old May 27, 2010 | 12:13 AM
  #8  
1998TA__1991RS's Avatar
Thread Starter
TECH Fanatic
iTrader: (23)
 
Joined: Nov 2004
Posts: 1,306
Likes: 0
Default

Originally Posted by MadIceV8
Did you hook it off of the vacuum hose that normally went to the air pump? As that hose has a little check valve in it that will prevent boost reading.
no, i have a single plane intake with eldebrock elbow, the back has a 90* brass fitting in it to go to the gauge, i dont think the hose is getting kinked due to it having plenty of vaccum on it at idle. i have the FPR referenced on the other side of the elbow the same way and it reads boost fine.
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-1

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-2

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-3

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-4

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-5

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-6

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
story-7

Awesome K5 Blazer Restomod Comes With C7 Corvette Power

 Verdad Gallardo
story-8

10 Camaros You Should Never Buy

 
story-9

10 LS Engine Myths That Refuse to Die

 Verdad Gallardo
Old May 27, 2010 | 01:21 AM
  #9  
75tonyA's Avatar
On The Tree
20 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (6)
 
Joined: Sep 2005
Posts: 165
Likes: 1
From: near chicago
Default

Maybe you can disconnect the brass fitting at the manifold and carefully blow air into the line to test it with an air compressor blow tip. I'd shut off the compressor and let most of the air out first to make sure you don't put too much air into the guage.

If the turbo is making boost and the car pulls hard, isolate the guage and test it.
Reply
Old May 27, 2010 | 05:22 PM
  #10  
98Camarod's Avatar
11 Second Club
iTrader: (43)
 
Joined: Aug 2006
Posts: 5,364
Likes: 2
From: Summerville, SC
Default

Is there a kink going through the firewall or once it gets into the cab?
Reply
Old May 27, 2010 | 08:37 PM
  #11  
BADBOB's Avatar
Staging Lane
iTrader: (3)
 
Joined: May 2009
Posts: 58
Likes: 0
Default

is the turbo maybe too small to be able to feed the engine with boost and the gauge at the same time?
Reply
Old May 27, 2010 | 08:50 PM
  #12  
NightHawk's Avatar
TECH Fanatic
iTrader: (1)
 
Joined: Jan 2003
Posts: 1,476
Likes: 0
From: Sarasota, FL
Default

I'm having the exact same problem with an autometer Z series boost gauge...shows vaccuum readings but even when the car is clearly into boost it doesn't register. I have mine referenced to the intake mani behind the throttle body.
Reply
Old May 27, 2010 | 09:16 PM
  #13  
lifeisgood's Avatar
11 Second Club
iTrader: (4)
 
Joined: Oct 2006
Posts: 1,029
Likes: 0
From: ky
Default

Originally Posted by BADBOB
is the turbo maybe too small to be able to feed the engine with boost and the gauge at the same time?
what? lol
Reply
Old May 27, 2010 | 09:50 PM
  #14  
BADBOB's Avatar
Staging Lane
iTrader: (3)
 
Joined: May 2009
Posts: 58
Likes: 0
Default

Originally Posted by lifeisgood
what? lol
see what happens is when the turbo is too small it can only feed the engine and isnt strong enough to push the boost through the small boost gauge line that far from the engine. Common issue for small turbo cars.
Reply
Old May 27, 2010 | 10:26 PM
  #15  
OUTLAWZ RACING's Avatar
TECH Addict
iTrader: (9)
 
Joined: Mar 2004
Posts: 2,726
Likes: 1
From: COLUMBUS GA.
Default

Originally Posted by badbob
see what happens is when the turbo is too small it can only feed the engine and isnt strong enough to push the boost through the small boost gauge line that far from the engine. Common issue for small turbo cars.
lmfao!!!!!
Reply
Old May 27, 2010 | 10:56 PM
  #16  
black98ws6ta's Avatar
TECH Addict
iTrader: (77)
 
Joined: May 2002
Posts: 2,107
Likes: 2
From: louisville,ky
Default

Originally Posted by OUTLAWZ RACING
lmfao!!!!!
x2
Reply
Old May 27, 2010 | 11:38 PM
  #17  
1998TA__1991RS's Avatar
Thread Starter
TECH Fanatic
iTrader: (23)
 
Joined: Nov 2004
Posts: 1,306
Likes: 0
Default

Originally Posted by BADBOB
see what happens is when the turbo is too small it can only feed the engine and isnt strong enough to push the boost through the small boost gauge line that far from the engine. Common issue for small turbo cars.
thanks rob, now finish my downpipe.....

back on topic...any other ideas
Reply
Old May 28, 2010 | 01:59 AM
  #18  
98Camarod's Avatar
11 Second Club
iTrader: (43)
 
Joined: Aug 2006
Posts: 5,364
Likes: 2
From: Summerville, SC
Default

How much of the small tube are you actually using before you tee it down?
Reply
Old May 28, 2010 | 02:15 AM
  #19  
Bird-Of-Prey's Avatar
TECH Enthusiast
iTrader: (23)
 
Joined: Apr 2005
Posts: 567
Likes: 0
From: Lebanon, OH
Default

Originally Posted by BADBOB
is the turbo maybe too small to be able to feed the engine with boost and the gauge at the same time?
Whoa! Alrighty then. I guess you do learn something new everyday .

Try referencing it before the TB and see what it reads. Curious myself. Boost leak possibly?
Reply
Old May 28, 2010 | 02:50 AM
  #20  
XtremeDime's Avatar
TECH Addict
iTrader: (16)
 
Joined: Jul 2005
Posts: 2,899
Likes: 0
From: Anchorage, ALASKA
Default

Originally Posted by black98ws6ta
x2
x3, hahah
Reply

Thread Tools
Search this Thread

All times are GMT -5. The time now is 07:33 AM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE