budmanv24

I need help with the vacuum lines on my 99 engine. I'm putting it in a boxster and some of the lines are disconnected and I'm having a hard time figuring where they all go. I have the vacuum canister, a 4 way tee, a one way valve, and then the switch for the secondary air injector. The car the engine is going into has a manual transmission. Correct me if I am wrong but does the vacuum line from the intake manifold go to the fuel rail? And I have another switch in the vacuum system that I am assuming is for an auto transmission that I can ditch. So where does the one way valve go in the system and which way does it face?

Macster

There is a vacuum line from the intake manifold to the vacuum fitting on the fuel pressure regulator mounted on one end of one of the fuel rails. Since the engine was from a 996 the intake might be turned the wrong way (I'm pretty sure it is) along with the fuel rails so the regulator is way far away. The vacuum line wants to be routed securely so it doesn't move around, chafe or flap around.

The Boxster Ecu has to be reprogrammed. At least one shop in Santa Monica knows abou this. Let's see...Claudio Szyszkowski's shop: Foreign Sport Technician.

I don't have the info handy here at home but I have several articles at my office that cover some of the issues of putting a 996 engine in a Boxster (2.5l Boxster). If you want send me PM with your email address and I'll send PDF files to you with the info. Perhaps you'll find it useful. Be sure your email in box can accept a big PDF file or two.

You'll probably need a Boxster Bentley manual that has some diagrams that give some info regarding vacuum line routing, connections.

I might have some diagrams that I can put in PDF form and send along.

Added: For the cost of one maybe 2 hour's labor you might see if a Porsche dealer tech would be of any help. You'll have to check/call ahead first and arrange to get the car there on a flat bed tow truck, but it might be worth the cost. One or two hours with some who knows these cars inside/out can save you lots of time and money.

Sincerely,

Macster.

budmanv24

I got the vacuum line from the manifold to the fuel rail, but its the ones from the canister to the secondary air injector switch and resonance valve are the ones that weren't connected when I got the motor so those are the ones I'm unsure about. The boxster vacuum lines are different since it doesn't have the resonance flap.

budmanv24

Ok, so as I have it plumbed right now I have one line going from the plenum to the fuel rail. Then I have a T at the vacuum canister with one line going through a switch and then to the secondary air solenoid. The other line going off the T goes through a one way valve, then a switch, then to the resonance valve actuator. Am I supposed to have a line coming off the one intake manifold (aka intake distributor) and going to the vacuum canister junction? There's just a hole in the manifold and it looks like there's supposed to be an elbow fitting in it. Because, if I am not mistaken, I have no source of vacuum on the canister right now.

Macster

I'm looking at a drawing of the 996 intake distributor (for a 3.4l engine) which has a vacuum canister mounted to it via a bracket. There's a short length of hose -- I'd estimate 12" or shorter -- shaped in a u-shape that appears to connect to a hole in the intake manifold and then to the canister.

While the hose has two different ends I can't tell from the drawing which end connects to the vacuum canister and which end connects to the intake manifold.

One end appears to have a plain tip that might fit into the intake manifold through a rubber seal/gromet while the other end appears to have some more complicated end.

IIRC there's some 996 (and other model Porsches) manuals located at:

http://www.cannell.co.uk/Manuals.htm

Run down the page until you come to the Porsche 996 section and grab the 996 Workshop manual -- Fuel and Exhaust.

The manuals are in PDF format. They are not complete and do not cover all 996 engines - for instance the 3.6l engine (although the GT3 is covered).

But with the drawings in front of you and with the engine and its manifold and other pieces in front of you perhaps you can work out what goes where and how.

I can email you PDF files -- I'll have to make them -- of whatever the Boxster factory manuals I have has to offer on the vacuum line routing.

Let me know by email if you want the applicable pages from the Boxster manuals sent to you.

Sincerely,

Macster.

Macster

Oh, I think I see where some confusion arises: Looking at the hardcopy pages I PDF and sent to you the other day I see on 24-8 there's a check valve that connects a small connector coming from one of the rubber connecting sleeves and this gets a vacuum line that runs to the fuel pressure regulator.

The item numbers on page 24-8 you want to pay particular attention to are: 4 (the sleeve), 8 (check valve -- read the note under the installation column on page 24-9 for the proper orientation of the check valve).

You can see the location of the pressure regulator and the vacuum connection to the intake's rubber sleeve in the drawing on page 24-5.

Sincerely,

Macster.

budmanv24

I have the porsche boxster workshop manual and the bentley boxster manual, but the vacuum lines in question are specific to the 996 engine due to the resonance flap. I looked at the 996 manuals on the cannell website and couldn't find any better diagrams than the porsche parts catalogs. I think I may not of received all the pdfs you sent me. I got Bark and Bite and Transplant Surgery. Were there other pdfs?

Macster

Sorry, got you mixed up with someone else I was helping with a fuel pressure regulator problem. The PDF file I mentioned is on its way to you.

Sincerely,

Macster.