Vacuum line clarification

[78F350]

In regard to the vacuum connections, here's that diagram, created with actual parts from a scrapped 2001 2.7L.

Notes:
-This picture shows what connections have to be made, the actual order of connections to the Y fittings (I) and (G) are not critical.
-The Tiptronic cars will have a 4-way connection at (I) or (G) with a line running to a changeover valve on the transmission.

It looks like a mess of tubes and parts, but in function it is fairly simple.
This shows 3 vacuum powered components: SAI, Resonance Flapper, and Fuel Pressure Regulator. Brake booster vacuum system is not shown.
SAI: Vacuum source -> electric change-over valve (E) -> change-over valve (D).
Resonance Flapper: Vacuum source -> electric change-over valve (J) -> vacuum unit (K).
Fuel Pressure Regulator: Vacuum source (B) -> Pressure regulator (C) -> injector valves (A).

Rubber sleeves (L) and (B) are the source of vacuum from the intake. (H) is a check valve. (F) is the vacuum reservoir.

[Brian in Tucson]

Originally Posted by 78F350

In regard to the vacuum connections, here's that diagram, created with actual parts from a scrapped 2001 2.7L.

Notes:
-This picture shows what connections have to be made, the actual order of connections to the Y fittings (I) and (G) are not critical.
-The Tiptronic cars will have a 4-way connection at (I) or (G) with a line running to a changeover valve on the transmission.

It looks like a mess of tubes and parts, but in function it is fairly simple.
This shows 3 vacuum powered components: SAI, Resonance Flapper, and Fuel Pressure Regulator. Brake booster vacuum system is not shown.
SAI: Vacuum source -> electric change-over valve (E) -> change-over valve (D).
Resonance Flapper: Vacuum source -> electric change-over valve (J) -> vacuum unit (K).
Fuel Pressure Regulator: Vacuum source (B) -> Pressure regulator (C) -> injector valves (A).

Rubber sleeves (L) and (B) are the source of vacuum from the intake. (H) is a check valve. (F) is the vacuum reservoir.

I know this is a kinda old post.Thank you for posting it. It is the clearest I've seen

If you're ever in Tucson, message me, I'll have a six pack with your name on it.

[boxfix]

I had a similar vacuum leak and SAI that would not reset.

Trying to get the 986 smogged in CA.


I had multiple vacuum leaks.

My vacuum reservoir was leaking. I put a vacuum hand pump and gauge on it with the reservoir in place and used long needle nose pliers to get the hose off and connect a test hose directly to the canister. It would not hold vacuum, but the replacement reservoir would hold vacuum.

New reservoir was like $22.

[you have to take the alternator out to reach the reservoir for R&R. I just put the second reservoir in the corner of the engine compartment and left the old one in ther unhooked from the vacuum system.]

I also had the at "L" not in the hole in the rubber part. I used a brass barbed fitting in the rubber manifold and high temp silicon tubing to connect the check valve.

I replace every bit of rubber hose I could with 3mm silicon hose.

I then inserted a vacuum gauge in the system with a "T" fitting. The manual says you should get from 12 to 19 inches of vacuum at idle. I had about 17.

Then all the "MONITORS" went away. If you have a Durametric you can see if the monitor pass or fail.

Be happy to answer any questions or PM me.

[thstone]

Originally Posted by 78F350

Thank you. Thank you. Thank you.

I needed this today to figure where the vacuum lines from the throttle body sleeves attach (H and C).