Hi guys, well they finally finished the 95SR I've been waiting to buy. What a nightmare, (I'll post the whole story when i get home but on the road in Vegas at moment).
Anyway, I've read several times about disconnecting the dreaded butterfly in the intake plenum to keep it from diving into the engine. Question is, exactly where is the vacuum line I need to plug off? I unfortunately don't have the shop manual yet and like everything else on this 3.5 motor, components are not exactly obvious. I believe LLoyd mentioned it was somewhere near the front of the motor under the plastic intake cover, but what does it look like and can someone give me a detailed description of where and what to do. Thanx in advance. Car appears to be super shape .

seer

Disconnecting will keep the shaft and blades from moving, but the only solution is to replace the lower intake plenum with the updated piece. Remove the grey plastic cover on the intake manifold. The vacuum diaphragm that actuates the shaft mounts to the forward end of the intake. You can disconnect the hose and plug it with a golf tee or similar plug. You will not get the same top end rush with this disconnected, but its only temporary until you can install the new lower plenum.

Lloyd was right, is just under the plastic cover in front of the intake, you can miss it. I belive the plug in green color. I drove mine for thousands of milages with that thing making noise but after reding a post of someone's breaking off and doing some serious engine damage I decided to disconnected. so far no side problems and runs much quite!

I'm going to be getting a 95 here soon also. Is this process something that is a "must do?"

It really is, people here have lost there engines on the way home from buying them. The 95 I bought 2 years ago with 56K was making so much noise it was ready to let go any second and I had to plug it before heading home.

So is this what everyone does(installing the new lower plenum), or do people just disconnect it and move on?

Disconnect and move on, since most of us are not made of cash!

I haven't heard of this problem, is it the same on the 96 SR?

I would definately not just disconnect it and move on! If a spark plug failed would you disconnect it and move on? <img src="/forums/images/graemlins/confused.gif" alt="" /> The plenum valves rotate at around 3000 rpm, allowing intake air to dive directly to the intake valves, taking the shortest route. Below this rpm, the intake air is pulled through the entire length of the intake plenum, boosting intake velocity and low rpm torque. If you unplug the diaphragm, the valves will always be in the position for low rpm operation, not allowing the enhanced breathing at high rpm.

The updated lower plenum costs about $275 as I recall and isn't all that hard to replace. I did mine along with a new timing belt and plugs/coils/wires in about three hours. Ran awesome when done, absolutely hauled ass. Why have the 3.5L unless you take advantage of that 3000-6000rpm breathing?

Besides, even if you unplug the damn thing, you're still going to have unfiltered air leaking into your intake!

If all the butterfly does is shorten the intake plenum runners, how is it that merely preventing the butterfly from opening results in "unfiltered air leaking into the intake"?

seer