A 8

This is a good question, any details on the offending valve that we can use to get a preventive action in place?

jimmyw

Transmission Coolant Valve - N488
It looks like the part has already been revised once: 4H0121670A
It is $165 and fairly easy to replace.

A 8

Good info, thx.

Mine smell of coolant sometimes and just realized this valve could be the leak. Those of you who have had a problem, was coolant smell a precursor to the car needing the coolant valve replaced etc?

A 8

Also, wanted to find out where the valve was and how it worked. Found this https://www.scribd.com/doc/94824363/...r-Transmission
Anyone know if its safe to pay and download?

jakematic

You'd be better off in my opinion to get SSPs and other factory manuals from erWin

jimmyw

That SSP in the scribd link only mentions the valve in a diagram since technically this valve is more of a cooling system component rather than a transmission part. Under the "Innovative Thermal Management (ITM)" section in the "2011 A8 Introduction" SSP there is a very detailed description and diagram of the whole coolant flow system and two blown up cutaway pictures of the valve opened and closed.

A 8

I know you pointed me to this once before but I could not get the site to work however tried internet explorer and not chrome yesterday and used it for an hour, very good thx.

jakematic

Excellent. Well worth the money in my opinion, especially if you save the PDFs

synchrocnc

OK, I took my car for a service today and asked if the N488/N509 valves could be checked for leakage, I was surprised to hear that my car doesn't have them, does anyone know why they wouldn't apply to a 4.2 TDI?

jimmyw

They might have been thinking you were talking about Coolant Shut-Off Valve N82 which is not installed in 8-cylinder TDI engines per the Audi repair manual.