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MAP SENSOR VACUUM

  • Thread starter Thread starter talladega500
  • Start date Start date Oct 16, 2018
T

talladega500

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Oct 16, 2018
#1
  • Oct 16, 2018
  • #1
I have a 1986 Mustang GT all stock, there is a white tee coming from the MAP SENSOR, do anybody know where the vacuum line connect. If I plug it the car will stall, with this off the car runs very rich.
 

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General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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Oct 16, 2018
#2
  • Oct 16, 2018
  • #2
What else has been done?
 
T

talladega500

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#3
  • Oct 16, 2018
  • #3
Nothing at all, any suggestions?
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
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Oct 16, 2018
#4
  • Oct 16, 2018
  • #4
talladega500 said:
Nothing at all, any suggestions?
Click to expand...


Are you still Speed Density or Mass Air?
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
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Oct 16, 2018
#5
  • Oct 16, 2018
  • #5
MAP sensor = Manifold Absolute Pressure = Speed density
BAP sensor = Barometric Absolute Pressure = Mass air

86-88 Cars read manifold pressure to adjust fuel/timing, while the mass air cars use the Mass air meter to directly sample it and use the BAP to reference atmospheric pressure to calculate density.

If the OP's car is still speed density, that port needed to be capped. Should be a direct line run from engine manifold to the sensor. If the car's been converted to mass air, you'll need to remove the line from the sensor and cap the vacuum line to the engine.

I bet there's other issues going on as well
 
Last edited: Oct 16, 2018
Reactions: 89ripper and Noobz347

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
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#6
  • Oct 16, 2018
  • #6
Mustang5L5 said:
Other way around.
Click to expand...

I saw it before you did. LoL
 
Reactions: Mustang5L5
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talladega500

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Oct 16, 2018
#7
  • Oct 16, 2018
  • #7
Noobz347 said:
Are you still Speed Density or Mass Air?
Click to expand...
Speed Density
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
43,270
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Box behind Walmart
Oct 16, 2018
#8
  • Oct 16, 2018
  • #8
talladega500 said:
Speed Density
Click to expand...
That sensor port goes directly to the manifold and nowhere else. It's the last place you want to splice into for a vacuum source.
 
T

talladega500

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Oct 16, 2018
#9
  • Oct 16, 2018
  • #9
Noobz347 said:
That sensor port goes directly to the manifold and nowhere else. It's the last place you want to splice into for a vacuum source.
Click to expand...
Thank you very much and I will correct that.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
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Oct 17, 2018
#10
  • Oct 17, 2018
  • #10
Remove that fitting and run a brand new vac line from MAP to manifold. NO taps at all into that line.

Perform idle reset procedure if car is stalling and run codes.
 
T

talladega500

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Oct 14, 2018
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Ellenwood, GA
Oct 17, 2018
#11
  • Oct 17, 2018
  • #11
Mustang5L5 said:
Remove that fitting and run a brand new vac line from MAP to manifold. NO taps at all into that line.

Perform idle reset procedure if car is stalling and run codes.
Click to expand...

That I will do and thank you very much
 
T

talladega500

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Oct 14, 2018
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Oct 17, 2018
#12
  • Oct 17, 2018
  • #12
That I will do and thank you very much
 
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