Howdy, Will try to keep this as short as possible. I have recently purchased a 2000 911 996 3.4L AT Convertible with a bad engine (out of the car and partially disassembled), but the rest of the car in pretty good condition. I was able to find and purchase a low milage 1999 3.4L M96 AT engine (long block) with RMS & IMS already done. So far, all good. I know that I need to use the intake, throttle body and wire harness from the 2000 car but what about the vacuum circuit? Is the 1999 VS 2000 3.4 M96 vacuum circuit and sensors the same on both engines? I have been looking for a vacuum diagram for the M96 2000 3.4L but haven't been able to find it yet. Unfortunately, the 2000 3.4L engine that came with the car was partially dissembled so no way for me to reference between the 1999 and 2000 engine and add/remove as needed. Thanks in advance for any help. Nic
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YOUR RESEARCH996.1 - Installing 1999 996 3.4L engine in a 2000 996
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No difference in coupe or cab in vacuum or SAI,,, there is a "slight" difference in the "Tiptronic " models in vaccum lines and wiring, but that is not in question here...
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Does this help?
DB, that's helps, yes sir. Thank you! So the comments in the "vacuum lines" PDF are in reference to parts not found in the 1999 engine but existing in the 2000 engine? For example, # 20 line connecting to sensor # 18? The "Do not exist" comment below for items # 30, 27, 17...is that for the 1999 or the 2000 engine?
Both engines are identical "vacuum wise" , the only differences are the throttle body and associated wiring/plumbing/attachments to the throttle body
The extra vac line is for the switchable exhaust. U should hook the lines up the same as they were on your '99 per that diagram.
Great. Much appreciated guys. I'll get to work on this and report back if I get stuck! Thanks
Quotes source post: 19493520
Quick question: I just learned that the donor car (MY 1999) was a Coupe and not an Convertible, like mine. Is there any notable differences between the coupe and conv. vacuum wise? Also, Secondary Air Injection pump..all 996's came equipped with it, correct?
Quotes source post: 19493742
No difference in coupe or cab in vacuum or SAI,,, there is a "slight" difference in the "Tiptronic " models in vaccum lines and wiring, but that is not in question here...
Quotes source post: 19493752
Gotcha. Thanks. Please bear with me here: if I just pull the intake, TB and wiring harness from the donor 99 AT engine and install the 2000 AT intake, TB and wiring harness and keep all of the vacuum related items on the 99 engine in place (if possible to do so) that should cover most of the swap, or not?
Quotes source post: 19493794
Yep, and don't try to overthink it....a little common sense goes a looooong way....
I am in the middle of a starter and Y cable replacement on my 2000 911/ 996, I was very careful when removing the starter but later noticed the line pictured below which is hanging out just above where the starter sits, any ideas where this might go?
Quotes source post: 20499637
Looks like it goes to the rear intake plenum cross-over "flap motor" ....( it switches intake resonance at low RPM and switches again at 5200 RPM )........There should be a very small black plastic line that plugs into the rubber line coming from the changeover- valve at the front of the intake above the alternator..
Thank you!
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