Want to change the coolant of a 2003 220 CDI. Is the coolant drain a red plastic item

You should have an expansion vessel in the engine bay. Usually like a plastic bottle. Check that this connects to the radiator or coolant system before adding water

Hello,

The thermostat of a 2002 audi a4 is located between the engine and the radiator. The thermostat is small and crucial. It is meant for the vehicles cooling system. It moderates the flow of coolant into the engine by releasing it when the engine need it the most. The thermostat is designed to open its valve once the temperature of the engine reaches about 200 degrees F. Its purpose is to keep the engine running at a consistent temperature, allowing your Audi A4 to operate at peak performance.

If You are planning on replacing the thermostat, here are the steps to follow to replace them, try to get these instruments (Car ramps, 4-by-4 inch wood block, Metric socket wrench set, Socket extension, Pliers, Drain pan, Empty plastic container, Black marker, Towel, Emery cloth, Gasket seal) then follow the steps below:

1. Raise the front end of your Audi A4 by driving up on a set of car ramps and placing your vehicle in park.
2. Place a 4-by-4 inch wood block behind one of the rear tires to keep the vehicle from rolling backward.
3. Use a socket wrench to remove the pan that covers the bottom of the engine.
4. Locate the red plastic cap that was behind the pan that you just removed. This red cap is your radiator drain plug. Remove the radiator cap from the top of the radiator and then place a drain pan under the red drain plug and turn it with a pair of pliers to allow the coolant to drain completely from the radiator. Once the coolant has completely drained, turn the drain plug to close it off. Be careful when using the pliers on the drain plug that you do not snap the plug off.
5. Slide under the vehicle and locate the thermostat housing that is sitting just above the oil pan drain plug. Pour the drained coolant from the drain pan into an empty plastic container and label the container so that you do not reuse the expelled coolant. Place the empty drain pan under the thermostat housing before you attempt to remove the housing to allow the coolant from the engine to drain into it.
6. Remove the 10 mm bolts that hold the thermostat housing on the engine block with a metric socket wrench. Do not lay directly underneath the thermostat housing as the coolant from the engine will begin to drain as soon as you loosen the bolts on the housing. Keep a towel or cloth with you to clean off any spilled coolant .
7. Remove the thermostat housing from the engine and lift the old thermostat out of the housing. Use a piece of emery cloth to clean the face of the thermostat housing and the engine block where the housing is mounted from any remaining gasket material or debris.
8. Spread a layer of gasket seal around the face of the thermostat housing and place the new thermostat on the housing, with the thermostat spring facing out from the housing. Position the housing back on the engine block and secure it to the block with the bolts.
9. Replace the pan the sits across the bottom of the engine of your Audi A4 and then refill the radiator with coolant and put the radiator cap back on the radiator. Remove the wood block from the back tire of your vehicle. Turn the engine on and drive the Audi A4 off of the car ramps. Allow the engine to run at idle for a few minutes to verify that the thermostat is working properly and then shut the engine off.

Hope this helped. Thank You for using FixYa!!!

Not all cars have a drain port. if there isn't a petcock or plastic plug at the bottom right or left side of the radiator, just take the lower radiator hose loose to drain. OK?

look for a plastic plug where I have drawn the red circle below. It should screw out. If you don't have a plug there, you will have to disconnect the lower radiator hose to drain the coolant.

more than likely you do need to remove the guard. the drain is going to be at the bottom of the plastic tank on the radiator.

Mercedes makes it easy! Get a 10 quart oil pump and draw the oil out of the dipstick tube. The oil filter is on top so can be removed with a filter wrench and easily replaced. No need to jack the car up or crawel under. No fuss no mess and a 10 minute oil change!!!

Hi there its easy, first remove the radiator cap,
then you will need to remove the engine cover under the car held in by 8mm screws, then on the bottom of the radiator you will see a red plug, unscrew the plug with a flat head phillps screwdriver and coolant will start to drain, when it stops, reinstall everything in the reverse order and fill with new coolant!
Happy Motoring

lol.......Always be prepared......Yes more then likely it will. Have a very large drain pan under the radiator.

very common problem as it is made of plastic.. dealer item approx $50 , i believe there are 2 of these little elbows in that area , replace both of them.. you will have to drain the coolant and remove the tensioner to replace them.

remove the cap on the radiator or the header tank, use a plastic container that will hold about 4 ltrs of coolant, there should be a drain tap at the bottom of the radiator, if not you have to remove the hose clamp on the bottom hose and let the coolant drain out.
Replace the hose and clamp, top up the radiator and run the motor while checking the coolant level, if the level goes down a bit just top it back up and check over the next day.
hope this helps