3.2L FSI, How to drain and refill coolant
 

This guide is for information purpose only based on my experience with 2006 A6 Quattro with 3.2L FSI engine, VIN No. WAUDG74F96N03xxxx . Use them at your own risk.
I have no personal interest in any of products or companies I mentioned.
Please check the parts numbers with Audi dealer to make sure you get the latest level to fit your car’s VIN No.

Parts needed:
Coolant 1 Gallon G-012-A8F-A4
Tools: Screwdriver
Pliers
It is necessary to remove the coolant crossover pipe when removing and replacing a high pressure fuel pump (HPFP). That job forced me to drain and refill coolant.
https://www.audiworld.com/forums/sho....php?t=2765010


Removal:
Remove underbody shield. In addition to screws to underbody, 4 screws to fascia and 3 plastic screws at the bottom wheel well on both sides need to me removed. You can use a quarter to remove them, and there is no need to remove front tires. I believe they are all ½ turn quick release.

Put a catch basket underneath and open the drain valve on lower hose. Turn the valve 1/4 turn CCW. Near the end of the turn, valve core will come out of the valve body. Use a flat screwdriver to push straight out 1/4 inch as coolant will start dripping.
Attachment 79865

Remove the seal around cowl cover and pull out the cowl cover – no fasteners
Remove the coolant bleed screw on the hose near brake fluid reservoir. Open the cap on the coolant reservoir too.
Attachment 79866

Put a catch basket underneath. Slide the clamp off and disconnect the rear hose to the oil cooler. About 1 more quart of coolant will come out.
Thanks for oaktreelimb for this valuable tip:
https://www.audiworld.com/forums/sho....php?t=2763323
https://www.audiworld.com/forums/sho....php?t=2763323

http://i249.photobucket.com/albums/g...4076marked.jpg

Installation note:
Lock the drain valve on lower radiator hose. Push in the valve first, then turn it CW 1/4 turn to lock it. It will go into housing a little further and lock. It is important not to force it and turn past the stop position, or o-ring will be damaged. If it doesn’t lock, realign to open position and try it again. Audi doesn’t sell the o-ring separately, and you are not going to be happy if you damage it and have coolant leak.

Install hose for oil cooler and reposition the clamp.
Fill the coolant reservoir with 50-50 mix of new coolant until all air comes out of the bleed hole. Install the screw for the bleed hole.
You may have to warm up the engine and add some more coolant for a couple of times to eliminate air pocket.

I used this coolant fill tool, which needs air compressor. I like it a lot because I don’t have to worry about air pocket causing engine overheat, and it takes less then 5 minutes to fill coolant including leak check.
Attachment 79867

http://image.snapon.com/internationa...ADKITPLUSA.pdf

Mine is Bluepoint (sold as Snapon), but I saw some other cheaper brand.
http://search.cartserver.com/search/...l=AND&go=GO%21

My car took 7.5 quarts total. Since specification is 10 quarts, I am guessing some old coolant was still in the system even after all draining procedures I followed.

The above instructions are great. One additional thing I did to expel as much coolant as possible was:
- before disconnecting the oil cooler hose, I cleaned off the neck of the reservoir bottle and then put my mouth on the bottle neck to form a seal and blew into the bottle several time. This forced out additional fluid. I am sure that you could fabricate something for the bottle neck and then use an air-hose. Regardless, this helped purge old coolant

Nice.

Good instructions. However in my case - the drain tap on the lower radiator hose never worked. It just dripped coolant (drop by drop). I just yanked the lower rad hose off the radiator. But putting it back on was next to impossible. Used coolant as lube - no luck. a light spray of wd-40 did the trick (you have to be careful to not use too much of that stuff with the coolant).

Also, bentley manual says - turn on heater to HOT and run it - this opens some valves where coolant is stored. Same goes while filling coolant.

Problems with drain tap...
 

to Am_ver (and others) - the drain tap is tricky...my car is a 2008 and it was the first time I changed the coolant. As noted in directions, you need to turn 1/4 CCW to break open the tap. Then you need to "pull it out" to start the flow. This is the hard part since the seal may be frozen. The directions state to use a flat head screw driver (to get behind the tap's head to help pull it away from the pipe fitting. What I did was to get pliers to grab the "tab" on the tap's head and "jiggle" it a while until it pulled outward. Once this happens...the flow will start.
Yes...pulling the hose is a pain and do not recommend doing that if you can get the above to work.

pulling the hose is easy - putting it back on is a b1tch!!

Get a tube of silicone lubricant. Safe with the coolant, safe for the o-ring, is super slick, and is in paste form. The hoses just pop right on. I use Sili-glide from napa

Good to know - thanks for the info!

How much 50/50 coolant is required for the refill?

8 liters (8,45qt?) was enough on mine.
cheers/H