Loss of coolant

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Loss of coolant

Post by amer » Tue Oct 08, 2019 8:31 pm

Hi guys

My 212k awx is losing coolant, on a weekly basis, it takes around a litre of coolant before i see it between the min and max mark... there are no visible leaks.

I sometimes get the check coolant beep/message... (temp stays at 90)

A month ago the following were replaced: timing belt kit and water pump (TPS parts), aux belts, radiator (magneti marelli)... along with the coolant temp sensor (what a difference to the performance with this! and no more engine rattle? hmm.)

It did use to eat a little coolant before, but not as much as around a litre every week... since the tb and wp replacement.. the loss has increased in my opinion..

So, took it back to the garage and on the ramp, and they said everything they have touched is intact, apart from a turbo pipe connection which had a gap, they connected that back as it should be.

So, the only area where we noticed coolant, was a slight coating on a pipe in the drivers side lower corner... the pipe is connected to some sort of mini radiator/cooler.. what is this part anyway and what does it do...?

Any suggestions of other possible culprits are appreciated..

The oil is coolant free... also the oil cooler was replaced at the beginning of the year... feel free to ask any questions!

Much appreciated, have a good week!


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Re: Loss of coolant

Post by maclee » Wed Oct 09, 2019 4:58 pm

I am far from knowledgeable about Diesels but there are plenty of professors here who will know for certain, but I am pretty sure that radiator is the charge air cooler (intercooler). If that is so, there will be no coolant in it, though it may be dripping there from somewhere above.

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Re: Loss of coolant

Post by ct.p » Wed Oct 09, 2019 8:58 pm

That is the fuel cooler as fitted to early 130hp PD TDI's.

You could completely bypass it if needs be. Your not going to drive it in Africa or anywhere really hot?
VCDS and Vagtacho in Maidenhead Berks

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Re: Loss of coolant

Post by amer » Wed Oct 09, 2019 11:49 pm

Lol haha nah just Glasgow and surrounding for now!

Is it easily bypassed..?

Came across this after a search..
desertstorm wrote:
Wed Aug 02, 2017 4:37 pm
Only the very early PD130's had a fuel cooler with a rad. The later ones have a fuel cooler but it's an aluminium pipe under the car. If you look under the drivers side you can see a black plastic cover with holes in it. remove the cover and you will see the cooler.
http://www.ebay.co.uk/itm/3B0203492A-VW ... 3076534608?

The cooler cools diesel going from the engine back to the tank. It can be very hot coming out of the engine and the tank is plastic. When the fuel level is low in the tank this may be an issue.Probably get away with it in this country but the temperature of the diesel does affect performance quite a bit. The ECU monitors the temperature and applies quite a correction factor dependent on the temperature. Hot is not so good.
So this is a cooler for the fuel going back... makes sense I suppose.. there is also a cooler on top of the fuel filter on the early ones..

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Re: Loss of coolant

Post by g3shabace » Thu Oct 10, 2019 10:49 am

Had a leak on avf engine took me a a loot of time to find.
My problem was on the back side of engine under tandem pump is a plastic adapter which was cracked. Very bad place needs patience to swap but it's a cheap fix I bought a whole kit for 7euro with new o-ring

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Re: Loss of coolant

Post by amer » Sat Oct 12, 2019 11:53 am

g3shabace, I will bear that in mind, thanks.


I believe number 7 is the problem, it is an additional water pump, managed to find one on ebay: click

I really hope replacing this cures my problem, like I said, we are unable to see leaks elsewhere... and going by this description I'm pretty sure I'm on the right track...
Is there a whining noise when your car is in idle? How about a coolant leak? If these symptoms are present, you need to check on the auxiliary water pump installed in your car. This pump helps to keep your coolant flowing in hot climates or under high loads on the engine or heating system.

Although your car can still function efficiently even if this part is malfunctioning, it would be very uncomfortable knowing there's something wrong with your vehicle. So for your peace of mind, it would be best to replace this malfunctioning component with one of the best and long-lasting products that ECS offers.

Keep your car cool and running properly by replacing your broken or not working auxiliary water pump with this new unit.

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