Engine MAP vacuum location?! (See pics)

jstang209

Dirt-Old 20+Year Member
Jun 3, 2004
640
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18
Stockton 209
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? 529EB607-53E1-41FA-AC16-FA4F4A7E2D88.jpeg 975318C8-BF7D-4951-A4C0-BFEA53B95530.jpeg 78BFE2F6-C622-40BD-804A-4457B0C32B31.jpeg 05DFD8E8-6E61-42F6-9A13-6FE3C2192301.jpeg B9822D51-8D75-4AEC-81F1-104E8E21889D.jpeg
 
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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?
 
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.
 
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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.