Specs Cars

How to Install a Boost Gauge on an Audi

1. Choose which vent you are going to install the gauge in and remove it by pulling it out. Inspect the vent to see if the gauge will fit into it. You may have to trim the rear flap of the vent to allow the gauge to sit in it.
2. Hold the boost gauge against the vent and draw a circle with a pen or white pencil around it to mark where the cut is going to go.
3. Use a dremel with a small cutting wheel and carefully trim the hole that you have traced. Test fit the gauge to make sure it fits in the trimmed hole very snugly. Smooth any rough edges with sandpaper.
4. Drill a small hole in the ducting that leads to the vent to allow the pressure tube for the gauge to go through. Run the tube through it. This should be included with the gauge.
5. Remove the trim located below the steering wheel and remove it. There are probably three or four 8-mm nuts.
6. Open the hood. At the rear of the engine on the left side of the brake fluid reservoir are two rubber seals. Remove them both, exposing two holes.
7. From under the steering column, route the gauge tube through the holes. Make small holes in the rubber seals for the tube. Run the tube through the seals and then reinstall the seals.
8. Connect the gauge to the intake manifold by cutting the hose that goes to the fuel pressure regulator and installing a T adapter for the gauge hose.
9. Hook up the power wire for the gauge to an existing wiring harness that goes to the factory gauges. Ground the black wire that is on the gauge to a suitable ground in the dash. Reinstall the vent and gauge and test it to make sure it works.