Vacuum leaks

I bought my smoke machine from Craigs List for $300. They normally cost $1000 new. Maybe check ebay too. If you google vacuum leak smoke machine you will get a lot of ideas. Here is a video on using a smoke machine.
 
I used 4" PVC pipe and rubber couplings from Home Depot and a end cap threaded a air chuck fitting on the end (in place of CAI). Turned my air compressor down to 15-20 lbs and pressurized the system (I found EGR block off plate leaking) You can use a long plastic pipe (like a straw size) to hear for slight leaks. If you have a Alky system, don't forget to shut it off. Good luck
 
Start the car, spray carb cleaner around all the gaskets, fittings, hoses, etc and listen for the difference in idle. Finds 99% of the leaks, costs ~$2.
 
I have never had luck with, carb, brake clean, propane, water etc on a TB. Best method I found is like mentioned above with the rockers pulled and psi'ing the intake.
 
Smoke machine works best If there is dye in the smoke its even better. I have the red line smoke machine that uses baby oil.Most take a special oil that costs alot of cash.If your looking for lower intake leaks you can block off pcv and breather holes and put a vacuum guage on the did stick tube.Sounds stupid but it works. Carb spray works good. The best way is to spray and have a scan tool so you watch fuel trims or wide band. Dont always get idle flare if its a small leak. good luck
 
Look at the thread I just posted "AMAZING DISCOVERY". I ordered that pre- made intake air tester with clamps from silicone intakes online.
 
Look at the thread I just posted "AMAZING DISCOVERY". I ordered that pre- made intake air tester with clamps from silicone intakes online.
That's a nice unit. I made the same thing from Home Depot plumbing isle. I wanted to confirm there were no leaks going thru the charge piping and inter-cooler so I just closed all the valves. Nice find!!!
 
That's a nice unit. I made the same thing from Home Depot plumbing isle. I wanted to confirm there were no leaks going thru the charge piping and inter-cooler so I just closed all the valves. Nice find!!!

I tried finding something at Home Depot, but never could find anything to correctly fit over the TB opening.
 
Plumbing isle. They have have plumbers call "fernco" It's a rubber coupling and they have different sizes and even reducers. Then use white PVC (plumbing waste pipe) HD carries 4" down to 1/2" and build from there. I pressurized mine from the turbo
 
I made one from a cheap blue plunger from Lowes (plumbing isle). Just remove the wooden handle.
 
I also fabbed one out of a PVC end cap. One of the best things I ever did for troubleshooting the car.

Found out:
Throttle shaft seals only leaked in the WOT position - at idle position they were fine.
IC to up-pipe hose was leaking only past 12 psi.
Plenum was leaking at the rear bolt.

With enough hose to get a regulator in the cabin, you can also test your alky spray point, or check how well your boost gauge tracks with Powerlogger.

I've often wondered if you could check exhaust leaks by doing the same thing at the downpipe outlet.
 
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