D-Jet Help - Please, Engine wont go below 3k Options

[Cupomeat]

Hello 914World, While I answer a lot of questions, I rarely post, BUT I am not well versed in D-Jet. I am having an issue that seems like it should have a simple answer, but so far, I am missing it.
So I am putting back together a 2.0L recently rebuilt for a friend and once I got it all back together, and once it started, the engine won't come down below 3K RPM. (IMG:style_emoticons/default/WTF.gif)

I am assuming this is some kind of Vacuum leak, maybe? It runs strong and smooth at 3K but doesn't go down with closed throttle.

SO, the engine is all new and I need to break in the cam, which, while 3k is probably ok, I'd like to get it sorted before I do that 15 min of 2k RPM.

I've checked all the vacuum lines and connections and see nothing wrong. I am thinking to get a smoke machine, or similar to try to see what I may have missed.

I am an L-Jet Guy with little experience with D-Jet and would LOVE some pointers or suggestions. (IMG:style_emoticons/default/pray.gif)

Thank you in advance and I did do some searches and haven't yet found anything like this.

CupO'Meat!

(the car is a 74 2.0L and I used Jeff Bowlsby's vacuum line diagram to double check)

[Dave_Darling]

Advanced ignition timing will raise the idle RPM, but 3K is probably more than that could account for. You have a vacuum leak somewhere--and very likely, it's a hose that is not connected to anything or a hose fitting that doesn't have anything attached to it.

Carefully look at the plenum. (The "intake air distributor" as it is called in the manuals, or the manifold if you're old fashioned.) Look for holes or fittings. There should be none that are open. Also look at the top and bottom of the plenum--there are two posts inside it to help support the top of it, and cracks can develop around where those posts attach. We have also heard of cracks forming in the flange where the top and bottom half are joined.

Make sure you don't have any hoses that are not connected to anything. (Possible exception: If your throttle body only has one small fitting on it, the vacuum advance fitting on the distributor dashpot does not get connected to anything.)

You have a vacuum leak. Find it and the idle should come down.

--DD