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Is it even a vacuum line? Ive been sorting out some wiring for my FC and found this in a bag of parts the previous owner gave me. One end looks to be cut...
Is it even a vacuum line? Ive been sorting out some wiring for my FC and found this in a bag of parts the previous owner gave me. One end looks to be cut...
Goes from the thermowax at the back of the TB to the double throttle diaphragm at the front of the TB.
So one end of it is cut, is there a replacement i can buy? What is this part called?
It's just a check valve. You can really use any style, as long as the direction of airflow is correct (air flows from the double throttle to the thermowax)
California car. . . ..I believe they are 450cc low impedance injectors from five O motorsports. .. . Or whatever stock flow rate injectors are used on a 86 N/A S4 460cc?
I bought some for the trailing only and at some point I need to change the leading as well. . . .But the car passes smog so I'm not going to touch it right now.
It doesn't stay that clean. . . .That is during an upper intake removal and I cleaned everything with a small wire toothbrush.
It looks as if that is the check valve that goes inline to the relief solenoid. . .If you look at the upper diagram, in the center just left of it, you will see a check valve inline with the relief solenoid. .It is located next to all the other solenoids on the right hand side of the engine. . ..Also, I think it is hooked to the wrong port on the thermowax valve. . See below.. . There could be a reason for that. The Double throttle diaphragm actuator might be bad which would explain why somebody hooked it up like they did. You should check it with a hand vacuum pump. . . The double throttle diaphragm gets actuated by vacuum through the thermowax valve when it is cold. . .When the thermowax valve gets warm, it closes the vacuum line and double throttle diaphragm valve opens up the secondary intake plates. . . .all that being said, most people wire the plates open, and eliminate the double throttle diaphragm while plugging the line down at the block so it doesn't suck air. . . . . The double throttle diaphragm is no longer available if your is bad. . . . . .It's sole purpose is to restrict air flow through the intake while the car is cold.to prevent somebody from damaging it if they went full tilt boogie on a freezing day before the engine is warm. You see that photo above showing the intake opening, its those brass plates in open position. They close when the car is cold and open up when the car is warm. . . .The DTD actuates them through vacuum controlled through the thermowax which comes from a port down below it on the side of the engine block.. . Hope this helps. .
08-08-23, 02:02 PM
