What is life like with your car? Let us know and win £500 in John Lewis vouchers | No thanks
Volkswagen Passat CC V6 coolant pump failure
I have a 2011 Volkswagen Passat CC 3.6 V6 and the V55 additional coolant pump is not running (aux pump) which should run when the engine is switched off to circulate coolant around the cylinder head. I have owned lots of VR6/1.8t engines before, some with pumps running some without.
I have removed the wiring and can see that the terminals are wet, so it has obviously leaked and shorted the pump out in a previous life. Would this pump not running have caused any long term engine damage with heat spots? The engine runs very hot and it has high mileage for its age, but I see no apparent evidence of damage elsewhere and the fans run fine etc.
I have removed the wiring and can see that the terminals are wet, so it has obviously leaked and shorted the pump out in a previous life. Would this pump not running have caused any long term engine damage with heat spots? The engine runs very hot and it has high mileage for its age, but I see no apparent evidence of damage elsewhere and the fans run fine etc.
Asked on 11 September 2014 by hjread
Answered by
Honest John
My worry is how did the terminals get wet? As you know (and are afraid of), the narrow angle VR6 has just one cylinder head, creating a very large, flat area for the head gasket to seal and the potential for head gasket failure that leads to hot spots and burned out pistons.
So, first job is to trace the source of the leak and possibly get your VAG independent to use a probe to look for any signs of coolant damage to the piston crowns. Everything might be allright, but better not to run the risk of losing the engine.
So, first job is to trace the source of the leak and possibly get your VAG independent to use a probe to look for any signs of coolant damage to the piston crowns. Everything might be allright, but better not to run the risk of losing the engine.
Looking for a garage you can trust? Honest John's Good Garage Guide has thousands of reader recommended garages, plus how-to guides and tips on servicing.
The Good Garage GuideSimilar questions
I have a 17-month-old SEAT Ateca 1.5 TSI. I thought the radiator needed topping up but stupidly mixed the antifreeze 50/50 with water when it was already premixed. How would this small amount affect the...
Should the fan run continually when the engine is running or only when coolant reaches a certain temperature?
I'm having some issues with my petrol Renault Clio Rush 1.2 8V. I had the water coolant tank and stop light show on my dashboard because the engine was overheating. I found there was no coolant in the...
Related models
.jpg?width=115&height=75&rmode=crop)
Very good looking, stylish alternative to the standard Passat. Coupe looks with plenty of rear passenger space. Quality improvements.
Elsewhere on 
.jpg)
