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Discussion Starter · #1 ·
Before I got the car smogged and all the smog equipment was put on it I usually had between 14-16 pounds of vacuum. After I now have about 6-7 lbs when idling in park and 10 when I let of the gas while driving. Is that normal? Shouldn't there be more?

Also, on a side note, the car is struggling to stay idling when I put it in drive. After it's been in drive and adjusts the car is fine but from park/reverse to drive it almost dies out and actually did die out the other day. I usually just give it a little gas to get the rpms up. What adjustment do I need to make?
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lag,what is that?
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Is this on the GN?

If it is, yes you should have around 16'' of vac. in park.

Sounds like you have a vac. leak somewhere.
 

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In park, about 19 cold, about 18 warmed up.
 

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Discussion Starter · #6 ·
Well I ziptied some connections and replaced the PCV and now my vacuum went from about 6 at idle to 9. So, I fixed a little, but I don't know where else to look for a leak. I checked all the hoses and they look to be pretty snug and they are new anyway. Maybe the vacuum block on top? All I know is before I had to get the car smogged with an EGR and Evap canister I used to get about 15. However, the BLM's are no longer 148, they now read 128.
 

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Discussion Starter · #7 ·
Well I ziptied some connections and replaced the PCV and now my vacuum went from about 6 at idle to 9. So, I fixed a little, but I don't know where else to look for a leak. I checked all the hoses and they look to be pretty snug and they are new anyway. Maybe the vacuum block on top? All I know is before I had to get the car smogged with an EGR and Evap canister I used to get about 15. However, the BLM's are no longer 148, they now read 128.
 

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You can try pinching off each vacuum line leading from the vacuum block and see if the vacuum increases. If it does, then check out the connections further down the line on that particular feed.

If nothing causes it to increase, then take some carb cleaner and spray around the base of the block, plenum, etc. and see if the vacuum increases which would indicate a leak at the point your were spraying at the time. Be sure the hose to the pcv is well connected.
 

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Since the vacuum was higher before you got "smogged"- I'm guessing that you had to hook up the EGR and the vapor cannister. Those two would be the logical first places to look for the vacuum leak.
 

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Get a small funnel and put a hose on it..about 2 feet. Funnel to ear and move the hose end around the lines..you will hear the leak.
Or..soapy water in a spray bottle and srap the lines with car running, it'll bubble at the leaks...
 

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Discussion Starter · #11 ·
I installed an EGR, an evap canister, and a catalytic converter. I have ziptied down every hose I can find on everything. I even installed a new billet vacuum block today and ziptied the new hoses down on both ends. My vacuum is still around 9 lbs. I'm figuring it has to be a plenum leak maybe? The gasket could be broken I assume. I'm just getting really irritated now, where else can I look?
 

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did you pinch off each hose that leaves the vacuum block?
 

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Get a mity-vac and check every vacuum line connected to the intake. If you find one that won't hold vacuum follow it to the next connection and test there. You can get done with this vauum leak problem.
 

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Discussion Starter · #14 ·
I have pinched off each hose but I guess I'll try it again. Someone said I could have a weak cylinder and to do a compression test. But that doens't make much since because all was normal before the smog equipment was added.
 

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No, it is very unlikely.

As suggested earlier, it is probably in one of the hoses that got connected for the smog check.

What I do myself....is to pull the hose "harness" off the vacuum block...stick a vacuum gauge on one of the ports on the vacuum block and plug the other ports with my fingers. If the vacuum is normal, then I know the problem is in the vacuum hoses somewhere and not a leak on the engine such as the throttlebody or plenum.

Just tying the hoses with tie wraps does not ensure there is no leak. If a hose is pulled out of the rubber connectors on the egr solenoid, or one of the hard plastic lines is broken, or the vacuum ball under the fender is not intact, then you still have leaks that were not fixed. Another possible problem is in the the steel lines that come off the block. Often one of them may have a crack in it. Particularly the one to the fuel pressure regulator.

BTW, boost is measured in pounds per square inch and vacuum is measured in inches of mercury...:D
 

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Discussion Starter · #16 ·
Well, I traced a lead and found that the evap canister (thing near the intake on the drivers side) had a leak from a fitting. So I just took it off since I don't have to worry about emissions for a while anyway and plugged the hole up. Now I went from 9-14-ish inches of vacuum. Now to find the other 3 or so. Maybe it's missing in the FPR?
 
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