What did you do to your NNBS GMT900 Tahoe/Yukon Today?

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the_tool_man

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How did you get the smoke (from party smoker) into the EVAP port on the motor?

I didn't use it for that. I was tracking down vacuum leaks on my '77 Datsun. But I would imagine the process is generally similar:

1: Plug all of the openings into the system except for one.
2: Inject the smoke into that opening.
3: Look for smoke leaking out of the system.

I sealed off the intake inlet from the air flow meter, plugged the EGR valve, and hooked the vacuum line from the brake booster to the outlet of the smoke generator. I will confess that in reality, getting a good seal everywhere can be a challenge, or even impossible. In my example, the intake plenum couldn't be totally sealed because at least one intake valve was open at all times. But in practice, I was able to keep the rate of smoke going in high enough that even with known leakage through the engine, I could spot one major leak and a couple of minor ones.
 
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swathdiver

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After pricing a "professional" diagnostic smoke generator, I borrowed an inexpensive smoke machine, like the ones used for Halloween, from a friend. Worked great for finding vacuum leaks. They cost ~$30.

How did you get the smoke (from party smoker) into the EVAP port on the motor?
I didn't use it for that. I was tracking down vacuum leaks on my '77 Datsun. But I would imagine the process is generally similar:

1: Plug all of the openings into the system except for one.
2: Inject the smoke into that opening.
3: Look for smoke leaking out of the system.

I sealed off the intake inlet from the air flow meter, plugged the EGR valve, and hooked the vacuum line from the brake booster to the outlet of the smoke generator. I will confess that in reality, getting a good seal everywhere can be a challenge, or even impossible. In my example, the intake plenum couldn't be totally sealed because at least one intake valve was open at all times. But in practice, I was able to keep the rate of smoke going in high enough that even with known leakage through the engine, I could spot one major leak and a couple of minor ones.

Ok, I meant, how did you get the smoke from the machine into the car, I reckon shaping paper into a cone and tape and then into a hose and on from there.
 

The_Burban

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Paint can heating element, mineral oil and an air compressor. Start the oil smoking and push the air compressor through the smoke to introduce it into the engine. YT has plenty of vids on it.
 

R3cord303

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77177A01-C7C8-4E77-953A-2E1A0C6ED729.jpeg
H3 motor mount arrived today!

Paint can heating element, mineral oil and an air compressor. Start the oil smoking and push the air compressor through the smoke to introduce it into the engine. YT has plenty of vids on it.
I’ve never seen this but damn if it isnt a great idea.
 

Doubeleive

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Hooked up the tech2 and inflated the shocks to 18psi I will let it sit a while and see if it changes, I sprayed soap/water all over don't see any bubbles so far

***edit only been 10 minutes lost 4psi already but can't find the leak :mad:
 
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iamdub

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evap leaks are generally one of the 2 solenoids, the front solenoid runs about $25-30 online and can be changed in a matter of 2 minutes, the rear one runs about $35-50 and takes a few more minutes but is not difficult, the more pricier part is the canister which runs about $100 but probably doesn't need to be replaced unless your having trouble filling the gas tank.
for the time and prices involved to troubleshoot the leak you can shotgun it and replace all 3 and be done messing with it. just my .02, last time mine popped up it was just the front solenoid $25 and it went away

For the $160-$180 you'd spend on shotgunning it with parts and hoping for a solution, you could just have it tuned out and it'd be guaranteed to never be a problem again.
 

R3cord303

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Hooked up the tech2 and inflated the shocks to 18psi I will let it sit a while and see if it changes, I sprayed soap/water all over don't see any bubbles so far

***edit only been 10 minutes lost 4psi already but can't find the leak :mad:
Damn I need to get me a tech2. Saw the thread about how handy they are. Could it be leaking back thru the compressor?
 

Rocket Man

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for those that have the rear air shocks, do your shocks still have some air in them after an hour of sitting parked or do they deflate? I thought mine were holding air still even the next day after sitting overnight but now they are not, so I'm not sure anymore, curious if yours still hold some air even hours later, you can just reach under and squeeze the bladder to check.
Mine hold air for a long time, maybe months. I know when they deflate since it’s lowered, and it sat for at least 2 months last winter without losing air.
 

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