I've been using this setup for a while to test for vacuum leaks on my D2 and it's been working great, thought I'd share if anyone is interested.

Items required:
1. Harbor Freight Multi Use Transfer Pump

You can also find this at amazon for a little more money:
2. Swisher Sweets (Or thin cigar of choice).
3. Lighter

I've only used this setup with swisher sweets, as the mouth side of them is the perfect diameter to gently be pressed into the end of the red transfer pump hose. My discovery particularly enjoys the traditional red packs, but my buddy's '01 has a penchant for the blueberry flavor. Whatever flavor you choose, make sure your motor will enjoy it. Other small cigars/cigarillos will probably work, but I know for a fact the swishers are the perfect diameter for this application.

Instructions:
Remove a swisher sweet from the pack and gently wiggle the smaller round end into the end of one of the red transfer pump hoses. Attach the other side of this hose to the inlet of the transfer pump. Then under the hood of the car, remove the PCV/Oil Separator breather hose from the nipple on the intake manifold. Attach one end of the second red pump hose to this nipple, and insert the other end into the outlet side of the transfer pump. If you still have the factory plastic nipple, be extra cautious with this!! I've only tested with a replacement metal nipple and the PCV valve nipple from the Best4x4 mod, both of which were a tight fit for the red hose but worked without a hose clamp. Now on the throttle body side of the engine, disconnect the rubber throttle body intake pipe from the MAF, and stretch a rubber glove/balloon/other rubber device over the end of the hose to seal it off. This provides you with a visual confirmation that smoke is accumulating in the system and seals the intake off starting right after the MAF (metered air). With that, all your setup is complete!

Prop the hose end holding the cigar somewhere where the ash can fall and the cigar isn't resting against anything. I usually pull a bit of the hood trim up on the passenger side by the headlight and use that to hold it (see pics). Grab your lighter, light up the end of the cigar, and then begin furiously pumping the transfer pump to get the cigar going. When you have good smoke entering the system, you'll see the glove on the end of the intake pipe move with every pump cycle, and the cigar will quickly start burning down. If you go through pretty much a whole cigar and smoke starts coming out of the breather on your passenger VC that you removed from the intake manifold, congrats! You most likely don't have a vacuum leak. You can plug this line and keep adding smoke to the intake if you'd like, but I don't see a point for this just doing a vacuum test. When my car got to this point, the glove on the intake was partway inflated and holding pressure, so I decided that was good.

Plan for 2 cigars per test. The first one lets you "prime" the entire intake system, and then if you have a leak, the second one lets you slowly add smoke that will come out the leak location. Once the burning part of the cigar gets close to the rubber hose of the transfer pump it's inserted into, stop pumping. Gently pinch the hose below the cigar and slowly roll you fingers up to remove it. If you continue burning the cigar, you'll melt the hose (ask me how I know). Also, I bought a pump just for vacuum testing, since after you run one test it is really hard to get the smell out, and the cigars leave some tar residue inside. I've got a separate transfer pump for the trans/diff/tcase oil changes.

Here's some pics of the setup:


Removed my MAF to make clearance for the pipe. You can flex it up out of the way without removing the MAF, but my hose is old and brittle, probably like yours.



And that's it! I'm happy to answer any questions about the setup and any improvements are welcome! All in, the initial investment for this setup was 5$ plus an old glove I had, and an additional $2 for a 2-pack of swishers. That puts us at about $1-2 per test depending on your smoke volume, not bad!

 

That is awesome. I tried using a human friend of mine recently and it was a waste of time. This setup with the hand pump is nothing short of brilliant. Apart from Swisher Sweets smelling like ****, but it's probably the best tool for the job.

 

I think you're supposed to make the Swisher Sweet into a blunt first. So I'm told.