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Hello, I have a 79 280zxr and I am trying to figure out where the vacuum line hooks up at. The car runs very good after it is warm but struggles when cold. Thanks
 

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That is the anti-stall valve (i think) and I don't believe it is connected to anything - it pulls in extra air only in the event of a stall
how can it work if it's not connected? I wish I could find good diagrams for my car. chiltons is lame.
 

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That unit is in fact called a dash pot and if I had a dollar for every time I've seen a vacuum hose hooked up to it I could retire. If you put a vaccum hose on the dash pot, it will negate it's function. If you want to negate the dash pot function just take it off the car. You're better off without it anyway. It's function was to help lower the hydrocarbons on decceleration, by slowing down the rpm drop, making it almost impossible to slow down on compression with a manual trans. If you're in California with the smog nazi's, removing it won't make you fail an emissions test. That unit is not available anymore so you can legally take it off the car. Most of them are defective by now anyway. Z man of Washington
 

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That unit is in fact called a dash pot and if I had a dollar for every time I've seen a vacuum hose hooked up to it I could retire. If you put a vaccum hose on the dash pot, it will negate it's function. If you want to negate the dash pot function just take it off the car. You're better off without it anyway. It's function was to help lower the hydrocarbons on decceleration, by slowing down the rpm drop, making it almost impossible to slow down on compression with a manual trans. If you're in California with the smog nazi's, removing it won't make you fail an emissions test. That unit is not available anymore so you can legally take it off the car. Most of them are defective by now anyway. Z man of Washington
I believe you have this confused with the Boost Controlled Deceleration Device (B.C.D.D.) which hangs below the throttle body.
 

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Thanks espnluva2 for the kind words. I can be wrong once in awhile so I don't mind someone disagreeing with me as long as they're courteous which he was. chasincats, FYI, In this case I was definitely not wrong. The dashpot and the BCDD both work together towards similar ends. The BCDD function is for rpm's above 1200 approximately whereas the dashpot is for rpms from 1400 down to idle. By keeping the throttle plate from closing fast when it's released, it makes the HC's even lower when combined with the BCCD function for deceleration purposes. In either case you're better off without both of them. That's why I recommend removing the dashpot entirely, and eliminate the BCDD as well. That's why I offer modified throttle bodies where I remove all the BCDD hardware and weld the ports closed. Both systems have either already failed on most cars or they're going to be failing sometime down the road and they can cause dangerous scenarios when they do fail by not allowing the engine to idle down promptly. Usually when they fail, they won't let the rpm drop below about 2200, or else they won't drop until the car gets under 10 mph. They can also cause brakes to burn up as well. Z man of Washington
 
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