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Engine MAP vacuum location?! (See pics)

  • Thread starter Thread starter jstang209
  • Start date Start date Sep 12, 2023
J

jstang209

20+ Year Stangneter
Jun 3, 2004
640
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Stockton 209
Sep 12, 2023
#1
  • Sep 12, 2023
  • #1
Sorry I know this has been discussed several times but through everything I’ve found on here, google, and YouTube I’ve came across several different answers.

I have an 89 speed density 5.0

Currently the vac port on my MAP sensor is connected to the vacuum tee B/R port which apparently is supposed to be capped off. According to this diagram from LMR, it should be connected to one of ports on the back of the intake manifold. But currently out of those 3 ports on the tee on the manifold, one is going to the S port on the vacuum tee , one to the FPR, the other is going to the middle hose on the 5 piece vacuum diverter joint over on the passenger side( what do you guys call this thing). There is one more port on the back of the intake that is capped, should i uncap and run the MAP vacuum there (the ports are different sizes however) or should i remove the hose going from intake to passenger side diverter thing and run the MAP vac to the back of the intake. If I do that, what do I do with this middle hose of the diverter thing?
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,804
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Claremore, OK
Sep 12, 2023
#2
  • Sep 12, 2023
  • #2
I am not aware of a single stock 89 car being speed density. To my knowledge all 89 cars are mass air unless someone has specifically converted the car to speed density. So with that is this car a factory mass air car or has it been swapped to speed density?
 
J

jstang209

20+ Year Stangneter
Jun 3, 2004
640
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Sep 13, 2023
#3
  • Sep 13, 2023
  • #3
Car is speed density
 

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
Aug 25, 2016
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polk county florida
Sep 13, 2023
#4
  • Sep 13, 2023
  • #4
What computer is in it?
 
J

jstang209

20+ Year Stangneter
Jun 3, 2004
640
2
18
Stockton 209
Sep 13, 2023
#5
  • Sep 13, 2023
  • #5
this was an engine swap car, I believe donor car was an 88
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
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#6
  • Sep 13, 2023
  • #6
It doesn't matter too much where the sensor is plugged in. Plug it in as directly to the intake manifold as possible. The port that you showed capped will work great.
 
Reactions: jstang209

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
Aug 25, 2016
27,856
10,533
203
polk county florida
Sep 13, 2023
#7
  • Sep 13, 2023
  • #7
If it still has the A9L or A9P computer it will not work correctly without a MAF sensor.
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
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Box behind Walmart
Sep 13, 2023
#8
  • Sep 13, 2023
  • #8
Couple of questions:

Was this car ever running while in your possession?

If the SD system was swapped into this car, does that include the entire EEC harness as well? Changes have to be made if it's a MAF harness and SD EEC.
 
J

jstang209

20+ Year Stangneter
Jun 3, 2004
640
2
18
Stockton 209
Sep 14, 2023
#9
  • Sep 14, 2023
  • #9
engine is running great and just passed smog here in CA I just wanted to verify my hoses were hooked up correctly, thanks !!
 
Reactions: Noobz347
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