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Intake, Throttle, Manifold Q's?

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Not sure about the spring thing, but the butterfly in the throttle bodies on both my MJ and my Silverado are tilted. If you pulled the disc out, it would have an oval shape to close the round bore at an angle.

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Thanks...I messed up the post, but that answers the important question.

No kidding you messed it up. What was the question?


Ha Ha.  The original question(s) were:


Is the butterfly/throttle plate supposed to sit flat...in plane with the top/bottom of the TB...mine is at about a 10 degree angle.  Keyav8r seemed to confirm that it was normal.  I'm not really having any throttle problems, it just looks weird.




Is the pivot, where the throttle cable, cruise servo cable, and throttle linkage all connect...supposed to be spring loaded or just solely serve as a pivot/connection point? In other words, is it just supposed to flip-flop back and forth when the cables/linkage are disconnected?  There is a little "cylinder" at the connection to it, that looks like it would hold a spring or "keeper"


P.S. I'm still working on the intake/exhaust that I had to postpone for a week+ due to working OT and taking care of my wife after minor surgery.  Putting it all back together today...the project, not the wife.


Also, could you post, or PM me the procedure for the vacuum test to determine a possible cat blockage?  I'm thinking hornbrod's suggestion of a partially clogged cat could be the root of my slight overheat problem

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Your vacuum gauge should come with an instruction booklet outlining the procedure. Hook the vacuum gauge up to a source on the intake manifold. Start the engine and note the vacuum reading. Usually 17 to 21 inches of vacuum. Throttle the engine up to 2,000 to 2,500 RPM for 20 seconds or so and the vacuum reading should stabilize to the same reading you got at idle. Let the throttle snap shut. The vacuum reading should shoot up about 5 inches of vacuum higher for a second and then come quickly down to the original reading. If the vacuum reading stays high and comes down slowly with jerky needle movements, you have an exhaust restriction.

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