Metronet

For the 3.0 AVK owners, has anyone ever had a problem with the auxiliary water pump? I know I have it because my sticker has option code 8Z6 (Hot country) on it although I'm from Canada...

The pump is pretty expensive but I suspect mine might be bad. From time to time my temp gauge goes beyond 90C degree mark especially after car is driven on highway and parked. This is pretty much the only item that has not been replaced.

Part number is 06C121601

jcman

Yep I have the same code on my 04 AVK so I guess American models are in the Hot Country type too, I also noticed that the 8Z9 code is the Super Hot Country code for south America and Africa down markets.

You should be able to check the pump with vagcom or a direct 12 volt test when cold, but then again you might have a CTS issue.

Nialist

Is the aux water pumps primary purpose to keep cycling water after the ignition is turned off? And also as a back up in case of primary pump failure, of course, so the head wouldn't crack? When my aux water pump failed, everyone on the road could tell as it looked like the car pissed itself while throwing out a burst of steam 3m high. I'd listen to jcman and explore the CTS. It's only a fraction of the price of replacing the aux pump and 100 times easier.

Metronet

Thanks guys and sorry I should've been more specific. The CTS is new, genuine from Audi and also the symptom only happens with A/C is OFF while driving. However, if car is parked after highway driving than it obviously doesn't matter since A/C will be off hence the suspicion of the aux pump. Although I don't really know if the aux coolant pump is an after-run pump like the turbos or not. As a matter of fact it doesn't even show up in the bentley service manual lol

If A/C is on than it never gets past the 12 o'clock/90C degree mark while driving in stop & go traffic (or at least I've never noticed it). The PWM fan control unit was replaced a few years also.

Wow... and so it sounds like when the aux pump failed the 3.0 engine would overheat badly!

jcman

"Wow... and so it sounds like when the aux pump failed the 3.0 engine would overheat badly!" Not true, if the main water pump fails then trouble begins and you would know it because the cluster will scream red.


Your problem sounds very clear with the Aux Pump and yes it is an after run pump to even out heat on a hot shut-down, vacom is (should be)your friend.

jcman

[QUOTE=Nialist;24500292]Is the aux water pumps primary purpose to keep cycling water after the ignition is turned off?

:Yes

And also as a back up in case of primary pump failure, of course, so the head wouldn't crack?

:No


When my aux water pump failed, everyone on the road could tell as it looked like the car pissed itself while throwing out a burst of steam 3m high.

:Not related

Metronet

Thanks jcman, I'll look in that area now I found the after-run coolant pump V51 and coolant pump relay J151 in the manual.

You might be right about the CTS also. It seems like there is a dedicated CTS for the water pump! (really...?)

Part# 8D0959481B option code D2H which I also have (#17 in picture).

As a reference the water pump CTS for a B6 A4 engine code AVK is on the other side of the green sensor - Part# 06A919501A (#3A in picture).

jcman

No problem Metronet, I hope its as simple as the Aux CTS good luck

Metronet

Thanks, I'm gonna need it. I hope it'll be simple too lol

In regarding vag-com readings, there are no error codes. However, measuring block 132 shows there is error in system?

I was getting:

10000111 cooling fan on
10000011 cooling fan off


xxxxxxxx
│││││││└ Error in system
│││││││
││││││└ Thermostat actuation active
││││││
│││││└ Cooling fan triggering active
│││││
││││└ Control deviation
││││ 0 > specified temp.
││││ 1 < specified temp.
││││
│││└ Fan stage 2 active
││└ Fan stage 1 active
│└ not used
└ hot weather country

1: Description fulfilled
0: Description not fulfilled

jcman

What you are seeing as an error in the block readings might be a result in the aux pump or aux cts problems, our engines use two electric fans however once the engine is off these readings would be a mute point but running at certain hot re-starts without the aux pump or the sensor temp in range may throw a error on just that one part of the measuring block.

I would look for the Aux CTS measuring block, I never had the need to venture there and I'm most certain it exists.