Car Performance Specs

1. Place a floor jack under the transmission cross member and jack the front of the Audi off the ground. Place a jack stand on each A-Arm and lower the vehicle onto the jack stands. Make sure the emergency brake is in place or a wheel chuck is placed behind the rear tires to prevent the vehicle from rolling backwards while you work on it.
2. Place a drain pan under the petcock of the radiator and drain the radiator fluid into the pan. Depending on the age of the Audi, the petcock may be hard to open due to exposure to road dirt and salt over the years. Use a pair of pliers but be cautious as the valve easily breaks if excessive force is used. Once the fluid drained, close the petcock.
3. Trace the lower radiator hose from the radiator to the location where the hose connects to the engine. The location is to the right of the engine crank and may be difficult to see from under the vehicle. Depending on your comfort level, you may want to complete the rest of the job from the top of the engine, not the bottom.
4. Remove the radiator hose from the thermostat cover by squeezing the two metal tabs located together on the retention band clamp. A pair of needle-nose pliers is suggested for this task. With the tabs squeezed together, pull the radiator hose off the cover.
5. Remove the two bolts that secure the cover to the engine block with a boxed-end wrench. Unfortunately, there is not enough room for a ratchet. To remove the bolts, make short quarter turns of the wrench, as that is all that is possible in the limited space. With the bolts removed, pull the cover off the engine block.
6. Remove the gasket O-ring that fits into the bottom of the thermostat cover. If the cover does not have an O-ring, inspect the engine block for it. It sometimes sticks to the engine block.
7. Pull the thermostat out of the engine block. Take note that the end with the pin sticks out of the engine block. Place the new thermostat into the engine block so it sticks out in the same manner.
8. Place the thermostat cover back over the thermostat and thread the bolts in as far as you can with your fingers. Tighten the bolts with a boxed wrench.
9. Reattach the lower radiator hose to the thermostat cover. It helps to slide the clamp backwards on the hose and then push the hose onto the cover without the clamp. Then use the pliers to squeeze the tabs and slide the clamp into place.
10. Fill the radiator with a 50/50 mix of radiator fluid and distilled water.

1. Allow the 1.8T engine to cool for several hours so that you dont risk burning yourself. Then lift up the front end, using the jack, and put the car on a pair of jack stands. Put the drain pan underneath the front of the radiator and open the petcock on the radiator. Let all of the coolant empty into the drain pan.
2. Unbolt the thermostat housing from the bottom of the engine using a 3/8-inch ratchet, extension and socket. Pull the housing off of the engine, then make a mental note of the orientation of the thermostat. Pull the thermostat out of the housing and discard it.
3. Pull the o-ring out of the housing and install the replacement. Then install the replacement thermostat in the housing in the same orientation as the original. Bolt the housing back to the engine using the 3/8-inch ratchet, extension and socket.
4. Open the radiator cap. Fill the radiator with the 50-50 prediluted coolant. Lower the car off the stands using the jack. Start the car and let it run for 15 minutes with the heater set on high. Turn off the car and let it sit for an hour. Open the radiator cap and top off the radiator with the 50-50 prediluted coolant.