Tracking Down Vac Leaks w/ Smoke..

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Made a simple smoker to recently solve a very persistent, emissions-related, CEL on the sled. Then used it to smoke the intake + motor and discovered more than a few vac leaks.

The first was the oil dipstick tube o-ring. It had been in there long enough to harden and shrink. Replaced with new and now it seals well.

The second was an original rubber elbow, that had cracked on the inside of the 90° bend and being black was difficult to see. Smoke leaked out here, drawing my attention to it. I replaced it with a piece of blue silicone tubing. This metal line goes to the fuel pressure regulator, which is just above the passenger-side end of the steering rack.
V70_Vac%20Tree%20008_zpsd1mrc3yb.jpg


The third, fourth, fifth, etc. were all at the plastic vacuum tree. The tree caps were all hard-as-a-rock & brittle, thus loose and easily removed. Unfortunately I didn't have any vinyl caps on-hand that would fit. So I used some small, black silicone hose, doubled over one end, and zip-tied it closed.

One "branch" of the tree had broken off, and in-a-pinch, used a course-thread screw to seal it off. This time I used a fine-thread #6 brass screw + some red Loctite #518 sealant.

I also discovered the square-washer that fits on the vac tree where it slips into the aluminum intake manifold was also hard and shrunk and leaking. It's only held in place by a single 10mm bolt. Unable to obtain the correct replacement 0-ring, I sub'd a rubber one + some silicone grease. Ideally, wall thickness here would be 1.5mm. 2 was too thick, though I might have been able to press it home if I had some silicone grease while at the hardware store.

When I arrived home, I used Loctite #518 here to seal the tree to the I.M. Perhaps another product would be better?
V70_Vac%20Tree%20004_zps0blekxls.jpg


All of these leaks were downstream of the MAF sensor and therefore, un-metered. I have noticed a difference in performance under boost. Also hoping for a bit better gas mileage.

I should have built a smoker years ago.....what a time saver.
 
I'm contemplating buying a clearance Halloween fog machine, and creating the hosing/adapters myself to get the same effect as a $1k Pro machine

Anyone see any flaws in this idea?
 
How did you make your smoker?
Originally Posted By: sleddriver
Made a simple smoker to recently solve a very persistent, emissions-related, CEL on the sled. Then used it to smoke the intake + motor and discovered more than a few vac leaks.

The first was the oil dipstick tube o-ring. It had been in there long enough to harden and shrink. Replaced with new and now it seals well.

The second was an original rubber elbow, that had cracked on the inside of the 90° bend and being black was difficult to see. Smoke leaked out here, drawing my attention to it. I replaced it with a piece of blue silicone tubing. This metal line goes to the fuel pressure regulator, which is just above the passenger-side end of the steering rack.
V70_Vac%20Tree%20008_zpsd1mrc3yb.jpg


The third, fourth, fifth, etc. were all at the plastic vacuum tree. The tree caps were all hard-as-a-rock & brittle, thus loose and easily removed. Unfortunately I didn't have any vinyl caps on-hand that would fit. So I used some small, black silicone hose, doubled over one end, and zip-tied it closed.

One "branch" of the tree had broken off, and in-a-pinch, used a course-thread screw to seal it off. This time I used a fine-thread #6 brass screw + some red Loctite #518 sealant.

I also discovered the square-washer that fits on the vac tree where it slips into the aluminum intake manifold was also hard and shrunk and leaking. It's only held in place by a single 10mm bolt. Unable to obtain the correct replacement 0-ring, I sub'd a rubber one + some silicone grease. Ideally, wall thickness here would be 1.5mm. 2 was too thick, though I might have been able to press it home if I had some silicone grease while at the hardware store.

When I arrived home, I used Loctite #518 here to seal the tree to the I.M. Perhaps another product would be better?
V70_Vac%20Tree%20004_zps0blekxls.jpg


All of these leaks were downstream of the MAF sensor and therefore, un-metered. I have noticed a difference in performance under boost. Also hoping for a bit better gas mileage.

I should have built a smoker years ago.....what a time saver.
 
I hear if you have the jury rigging perk you can make one out of a pint paint can, a toaster, some scrap fittings, and a 2 psi max air regulator

If you're car has an evap port, snap on sells the female end for $50
 
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There is a guy selling smokers on Ebay he makes in a 1 gallon paint can. How did you make your smoker and how did you hook it up? I could use a smoker to troubleshoot a EVAP leak.
 
Originally Posted By: Leo99
There is a guy selling smokers on Ebay he makes in a 1 gallon paint can. How did you make your smoker and how did you hook it up? I could use a smoker to troubleshoot a EVAP leak.


Built a simple smoker using a new metal, gallon paint can, incense, silicone tubing, some brass fittings and an old aquarium pump.

I used a large blob of electricians putty in the bottom for weight and to hold the ends of a couple of firework "punks". Punched a hole in the side, down near where it meets the bottom for the air inlet from the pump. For the outlet, I punched a hole in the lid and affixed one of those Schraeder valves that's secured with a nut. I also removed the valve itself with a valve wrench. You could also just punch a hole and force the tubing in.

Very simple, but effective & a great time saver.
 
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