Vacuum Questions... for '89-'93 5.0

stangman16

Active Member
Nov 16, 2004
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San Antonio, TX
Can anyone help me out with identifying what these look like? I haven't a clue, I'm new to EFI engines and I'm converting over my '66 Mustang 302 to EFI. I'm trying to figure out the vacuum routing, and I don't know what or where the stuff numbered in the photo looks like/where it goes.

1. where the PCV valve connects to on the manifold (I know, pitiful, but I honestly have no clue about it)

2. EGR Vacuum regulator - I thought I bought an EGR eliminator kit (I have to check later) so I shouldn't even have this, right?

3. Vacuum Resservoir - where's it located in your car and what does it look like?

4. Diverter Valve from the - from the TAD solenoid, I don't have Cats, so where would this connect to the head at, and does it go to driver side or P/S? (got a photo?)

5. Bypass Valve - from the TAB solenoid. I don't have a smog pump, so does this just connect to the Diverter Valve? (got a photo?)

and also what does the Vacuum check valve look like?

Amazingly this is the hardest part of the conversion that I see and I'm trying to unfold before I get started on the vacuum section. I did pick up a vacuum tree from a local salvageyard, but I'm not sure if I'm going to need it. I have stock intake manifolds from a '91-93 Mustang GT.

ANY help would be of most help, thanks!
 

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All I can provide positive answers for is the pcv. It is located at the back on the lower intake manifold. There should be a large hole which would open up to the lifter valley, with a black plastic/rubber grommet in it. Be sure to use the pcv screen that goes under the grommet & pcv.

Without the EGR you should be able to just cap off that vac line.

I didn't know the fox bodies had a vac reservoir.
 
Can anyone help me direct where these need to be running to on the upper intake manifold? I had to borrow this pic from ebay, and my upper intake has the black hose aready connected where I drew it. Other then that I don't know where to route the other spots to...

I found out I can rid myself of the TAD/TAB solenoids with the EGR, so I'm definitly going to do that. Any help on where to route these, and what I can plug off?
 

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Vacuum is vacuum, so it really doesn't matter where you connect them. Just be sure to match the hoses sizes and cap the unused vacuum connections on the intake manifold.
 
Yep, got a few capped off myself! Keep one to the FPReg, well on that old car that's all I can think of? One of those goes to a charcoal canister for emissions purposes, one to the FPR, I think some go to the EGR but mine doesn't have EGR, one has to do with the brakes???

I think I have a diagram... hold on
 
The two small ones are the FP regulator which you want, and the other is the EGR which you can cap off. The one in the back is the PCV. The one in the front of the intake runs up front somewhere haha sorry never followed that one.