[rgh0]

I dont know why you would clamp off a hose to the auxiliary cooling pump without digging into the ridiculously complex coolant system in more detail but it certainly does not exist on my 2013 V8TDI. Clearly some other problem has been covered up by this.

Potentially the pump has failed and this was a quick fix to prevent back flow through it ?

cheers
Rohan

 

[rgh0]

Hi Both,
I appreciate your responses and confirming my fears.

What is the purpose of this auxiliary pump? What system does it support?
Given that I've now replaced the main and auxiliary pump, and the car runs too cold with the clamp removed. I'm after suggestions of what other parts may have failed that is allowing (I assume) water to bypass the thermostat and continue circulating through the radiator causing it to run too cold.

Any help is much appreciated. I'm likely way out of my depth here though and may just have to bite the bullet and take it to VW. It's frustrating that the car is not throwing any errors though so I'm not sure how quickly the cause will be identified and resolved.
Cheers,
Clutrz

The SSP 467 on the V8 TDI and also the Erwin manual section on the engine provide lots of details to understand what's going on. From a quick look it appears the electric pump in question is dedicated to the EGR cooler. I am not sure if there is a second electric pump somewhere for the internal cabin heater and transmission heating / cooling or whether these circuits come off the main pump or the EGR pump. The are lots of valves and a couple of thermostats at least that control how these circuits work. It would take me about 4 hours to figure it out with the manuals in hand and going over the actual piping circuits on the engine, i hope I never need to do it .

I suspect most mechanics ( VW dealer or independent) would take even longer to figure it out to diagnose your problem better, if they could be bothered which is probably why the clamp bodge fix.

cheers
Rohan

 

[rgh0]

Yes its there - take out a 1 hr subscription and print to PDF all the manual sections that relate to your cars VIN

cheers
Rohan