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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

Vaccum Sources under the dash.

  • Thread starter Thread starter mavmavv
  • Start date Start date Jun 24, 2008
M

mavmavv

New Member
Nov 21, 2007
185
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0
Jun 24, 2008
#1
  • Jun 24, 2008
  • #1
Welp, it certainly sounds like I have a vaccum leak under the dash.

If I remember correctly the only vaccum sources under there are the brakes and cruise control. I can hear the leak increasing as I push down on the brakes, but it could just be something rubbing on something else via the pedal.

Im gonna check under there at lunch and figured id check here to see what to look for.
 

bullitstang1313

Member
Jan 21, 2003
713
0
16
Indianapolis / Columbus, Indiana
Jun 24, 2008
#2
  • Jun 24, 2008
  • #2
Don't forget the air conditioning/heater controls.
 
M

mavmavv

New Member
Nov 21, 2007
185
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0
Jun 24, 2008
#3
  • Jun 24, 2008
  • #3
bullitstang1313 said:
Don't forget the air conditioning/heater controls.
Click to expand...

oops, yeah, forgot about that. I believe the noise is located right under the column though.
 

93 LX

Founding Member
Jun 2, 2000
3,081
3
0
Norwalk, CA.
Jun 24, 2008
#4
  • Jun 24, 2008
  • #4
power brake booster is leaking. Time to replace it.
 
M

mavmavv

New Member
Nov 21, 2007
185
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0
Jun 24, 2008
#5
  • Jun 24, 2008
  • #5
93 LX said:
power brake booster is leaking. Time to replace it.
Click to expand...

yeah, thats what I imagined it would be. I can hear it sucking during acceleration too.

*sigh* Minds well still check out the rest of the vaccum lines too.

The booster is a pretty easy swap though, right?
 

bullitstang1313

Member
Jan 21, 2003
713
0
16
Indianapolis / Columbus, Indiana
Jun 24, 2008
#6
  • Jun 24, 2008
  • #6
4 nuts under the dash. Kinda a pain to get to, but not really that difficult to do.
 

93 LX

Founding Member
Jun 2, 2000
3,081
3
0
Norwalk, CA.
Jun 24, 2008
#7
  • Jun 24, 2008
  • #7
an easy to be sure is to disconnect the booster and see if the hissing goes away. As far as changing it, it is easy only 4 bolts to remove. The trick is getting under the dash to do it.

Pull the MC out far enough to you can pull the booster out. the unbolt the 4 nuts that hold the booster to the firewall. You have to unhook the brake pedal from the booster but thats a simply tug on a clip. Its the clip that holds the brake light switch. Youll see when your under there.
 
M

mavmavv

New Member
Nov 21, 2007
185
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Jun 24, 2008
#8
  • Jun 24, 2008
  • #8
Ugh, I knew I had done this job before on my little sisters Honda.

I remember how big of a pain those stupid 4 bolts are.
 

93 LX

Founding Member
Jun 2, 2000
3,081
3
0
Norwalk, CA.
Jun 24, 2008
#9
  • Jun 24, 2008
  • #9
LOL yeppers however when i did this on my 82 it went quickly.
 
M

mavmavv

New Member
Nov 21, 2007
185
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0
Jun 24, 2008
#10
  • Jun 24, 2008
  • #10
Now am I going to have to rebleed the brakes also? I dont do much brake work, the master cylinder is self contained, right?
 

93 LX

Founding Member
Jun 2, 2000
3,081
3
0
Norwalk, CA.
Jun 25, 2008
#11
  • Jun 25, 2008
  • #11
I left my system intact so no bleeding was needed.
 
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