====== Vacuum Box (126 270 91 79) ======
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**Part number(s)**: 126 270 91 79 \\
**Used on**: 722.3, 722.4, 722.5
===== Removal =====
- Locate vacuum modulator on left side of transmission
- Unplug vacuum line from intake manifold
- Remove 2x 5mm allen screws holding bracket to transmission case
- Pull vacuum modulator out or pry gently with screwdriver
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Loosening screws on vacuum modulator
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Old vacuum modulator removed
===== Installation =====
- Clean the surface area on transmission case where vacuum modulator is installed
- Assemble vacuum modulator pieces
- Thrust pin
- Turn key and cap
- Mounting bracket
- O-ring
- Insert vacuum modulator assembly
- Tighten 2x 5mm allen screws
- Reattach vacuum line from intake manifold
- Replace old vacuum line parts if necessary
- 117 997 09 82 - Rubber vacuum connector
- 117 078 05 81 - Vacuum elbow
- 116 276 06 30 - Plastic vacuum line (black)
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Clean vacuum modulator mating surface
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New vacuum modulator installed
===== Adjustment =====
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- Disconnect vacuum line from modulator
- Plug the intake manifold line to prevent leak during testing
- Locate tester port near bottom right of vacuum modulator on transmission case. Remove 12mm hex screw cover.
- Thread pitch for this hole is M8x1.0. Use an engine oil pressure tester kit and connect the gauge to this port.
- Drive vehicle at 30mph with selector in D and read pressure value off gauge
- Although the proper procedure is to perform measurements while car is moving, the same pressure could be measured by idling in D at a complete stop.
- Adjust pressure by removing the turn key cap and turning the key clockwise or counter-clockwise
- Clockwise rotation increases pressure by approximately 6psi
- Counter-clockwise rotation decreases pressure by approximately 6psi
- When complete, remove testing gauges and reconnect vacuum line
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Engine oil pressure test kit
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Adapter we need for testing port.
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Pressure testing kit hooked up with an elbow piece
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Achieving 58psi @ 30mph