Where is the thermostat located on a 1995 Audi A6?

Answer

To gain access to the thermostat you will need to remove the top and front engine covers. You will need to remove the serpentine (ribbed) belt. Take a digital photo or draw a picture of the belt routing before you remove it so you will remember how it goes back on. Mark the direction of rotation on the belt so it can be put back on going in the same direction. Remove the belt by either using a 17mm wrench or socket or a 10mm hex (depending on idler type) to loosen the tension on the idler (clockwise). Insert a nail to small drift in the alignment holes to hold the idler in the loosened position. Remove the ribbed belt.

Remove the ribbed belt idler by loosening the 10mm hex head bolt that holds it to the engine block. This is done to facilitate removal of the outer left cam sprocket guard cover.

You will then need to remove the lower left most front grill piece (on the front bumper) to gain access to the radiator drain. I use a long piece of 3/8” I.D. rubber hose and push it over the radiator drain outlet and run it out through the right wheel well to a catch basin. Loosen the drain screw (large blue plastic) to drain the radiator. DO NOT remove the drain screw all the way. This whole draining exercise is easier if the car is up on ramps or jack stands and the belly pan is removed, but it is not necessary.

While the radiator is draining, loosen the timing belt idler pulley. This will slacken the timing belt enough for you to remove the thermostat housing.

The thermostat housing is a long cast aluminum piece with a large radiator hose connection at it's left most and two bolts that hold it to the block at its right.

Once the radiator is drained, remove the lower radiator hose from the thermostat housing. Remove the smaller oil cooler coolant hose from the thermostat housing as well.

Remove the two bolts holding the thermostat housing to the block and remove it by pulling it straight out from the block then out to the left under the timing belt. The thermostat will be staring you in the face, sticking out of the block directly above the cam belt idler.

When replacing the thermostat, be sure to replace the rubber o-ring as well. Also be sure that the thermostat is rotated so that the air bleeder is on the top. Torque the bolts holding the housing to the block to 10Nm (7 ft-lbs).

Re-install everything in the reverse order of removal. When tensioning the timing belt, check the tension by twisting the belt at its longest span. You should just be able to twist it 90 degrees. Be sure the cam sprockets do not rotate during the tensioning.

Remember to close the radiator drain screw and re-fill the cooling system.

Best of luck.

First answer by ID1074558091. Last edit by ID1074558091. Question popularity: 54 [recommend question]