Hi, 

I recently bought the above vehicle on 143k miles for what seemed like a good price from a local second hand car dealer. 

 

I've not been able to put any decent miles on it yet, but was a little concerned by the strong smell originating in the engine bay, followed by noticing a dried creamy residue down the side of the coolant bottle and onto the chassis. 

 

 

 

On my first drive the coolant warning light came on and the level on a slope was just shy of the sensor. Looking at the fluid though, it didn't look in the best of conditions. Reading through the service history; the second timing belt and water pump was carried out at 118049 miles on 18-01-2023.

 

Initial VCDS scan did bring up:

 

28253 - Coolant Pump 3

P26F8 00 [00100000] - Stuck

Intermittent - Not Confirmed - Tested Since Memory Clear. 

 

And this was dated the day after I ran the scan bizzarly.

 

No faults have since been logged after a few short drives. 

 

After reading plenty on here regarding water pumps and silikat coolant bottles, I wondered if anyone could shed any light on the coolant pump 3?

 

Thanks for any help with this! 

 

My guess would be your heater matrix is blocked forcing coolant out the overflow of your reservoir. Have a google and you’ll find plenty of threads about it 

Ohh and coolant pump 3 is towards the back of the engine at the bottom. The other electric pump is towards the front just below the oil filter which pumps coolant around the charge cooler circuit. The coolant circuits are quite complicated on these engines 

Thanks T07 for the location info regarding the additional coolant pumps. 

 

I agree that a blocked heater matrix sounds highly likely; perhaps this coolant bottle is the type with the sandwiched Silikat pouches. 

 

I'm a little concerned at the smell in the engine bay, so was looking to work through all possibilities for this. 

The coolant pump3 fault I thought a good place to start; are they known for causing issues? 

 

I'm thinking an exhaust gas test on the coolant be wise, and an overnight pressure test. 

Any other suggestions? 

 

Thanks for any help with this

5 hours ago, Whitie said:

perhaps this coolant bottle is the type with the sandwiched Silikat pouches.

Well, those are helpfully labelled "mit silikat".

I see, any other reasons I should be looking into for a blocked heater matrix then can you suggest? 

Thanks 

A different engine, but no cabin heating was the first symptom of my TSI's coolant check valve failing:

It wasn't a great experience 🙄

 

Gaz

Thanks for your input Gaz, I wonder how different the diesel cooling system is. 

Sorry to hear you had such a hard time with it all! 

The thread I found linked within had one contributor mention they had their electric water pumps replaced as a consequence of a similar issue, along with their heater matrix, this could be why I came across that fault code. 

With 143k on the clock, I may have a different coolant bottle on this car now and the silica bag may have burst prior.... Great. 

Quick update on this in the hope of other people's experiences pointing me in the correct direction. 

 

The supplying garage have stated that since 30days from sale have passed, it'll be a 50/50 split on any work carried out. They also can not get me an appointment at their place of repair for 2-3weeks; hardly ideal as our first child is expected in the next 10days.

 

They've suggested that they're happy to supply me with a heater matrix if I'm happy to fit it. 

 

My concern is that there is more than just the heater matrix damaged/faulty here. Looks like the system has overheated so much, the coolant bottle has distorted. 

Yesterday I used a RELD kit to test the coolant for CO²: unfortunately the result was positive for the gas. 

 

I don't have a pressure tester as yet, but maybe a compression test would also be helpful to rule out leaks into the cylinders. 

I'm also thinking of bypassing the EGR and charge coolers to rule them out. 

 

Thanks for any assistance with this. 

I would be rejecting the car and asking for a refund. Coolant issues are a nightmare on these engines. 

 

https://www.moneyhelper.org.uk/en/everyday-money/buying-and-running-a-car/your-rights-if-something-is-wrong-with-your-car

4 hours ago, Whitie said:

The supplying garage have stated that since 30days from sale have passed, it'll be a 50/50 split on any work carried out.

 

I don't think this is correct.  See here:

https://www.themotorombudsman.org/knowledge-base/what-are-a-consumers-legal-rights-when-buying-a-car

 

'If you are now outside of the first 30 days, the seller has one opportunity only to repair or replace the faulty car. You will not be able to ask for rejection at this stage. This does not apply to cars purchased before 1 October 2015. The Sale of Goods Act allows the seller to either repair or replace the car within a reasonable period of time without causing significant inconvenience.

If you are complaining about a fault within the first six months of purchase, it is presumed this fault was there at the time of purchase. The seller will need to prove that this fault was not there at point of sale. If you are complaining about a fault outside of the first six months, you will need to prove that fault was there at point of sale.

If the seller is unable to repair the fault because the same fault persists or a new inherent fault has developed, or the replacement car has an inherent fault, then you can ask for your money back or a price reduction (partial refund) if you wish to keep the car.

Remember, for rejection outside of the first 30 days, the seller is entitled to deduct the mileage you have added onto the car.'

 

And:

 

https://www.autotrader.co.uk/content/advice/how-does-the-consumer-rights-act-protect-you-when-you-buy-a-car

 

'The Consumer Rights Act stipulates that dealers will only get one chance to repair or replace the product, so dealers can’t make multiple attempts to fix a problem unless otherwise agreed. If they fail to remedy the fault in one attempt or within a reasonable time period, you’ll be entitled to a full or partial refund. Alternatively, you can ask for another attempt at repairing/ replacing or for financial compensation. The law says, in almost every case, there can be no reductions from any refund given in the first six months. However, motor vehicles are the one exception, where the seller can make a ‘reasonable’ reduction for the amount the car has been used.'

 

2 hours ago, T07 said:

I would be rejecting the car and asking for a refund. Coolant issues are a nightmare on these engines. 

 

https://www.moneyhelper.org.uk/en/everyday-money/buying-and-running-a-car/your-rights-if-something-is-wrong-with-your-car

 

Agreed, although it looks like @Whitie needs to allow the seller '..one opportunity only..' to repair or replace it first - 'without causing significant inconvenience'.

 

I think it'd be sensible for Whitie to seek advice from Trading Standards/Consumer Direct at this point 

 

Gaz

 

Edited 7 July, 20241 yr by Gaz
additional comment

Thanks Gaz, that is what I also read online when looking this bizzare clause up. 

As you say, the 30days means I can not simply reject the car. 

It is written in to their paperwork that the repair would be split 50/50, and the repair workshop of their choice would have to be used, with me being responsible for taking the vehicle there. 

Since they do not have appointments available for another fortnight, and our first child due in less than a week, I feel stuck in a difficult situation. 

They have offered to purchase the heater matrix and I would fit, but I'm not convinced only the heater matrix is damaged in this case. 

 

So I ordered a block tester, which changed colour within a few minutes. 

This has prompted me to systematically test components in the coolant system: so far I've drained the system and tried to flush the matrix; completely blocked. 

Checked the bottle for silica bag; nothing in the central cavity, but plenty of grit in the pipework. 

I then removed the EGR valve/cooler to test for blockages and leaks as we used to when I worked on these machines for a living. No leaks evident up to 1.4bar of pressure, but cold. Very clean looking also, hopefully as it was doing 20k a year before I got it recently. 

Next up I was going to remove and test the charge cooler in a similar fashion. 

I'm not convinced there's a headgasket/crack in the cylinder/head as I haven't witnessed any overheating, but I won't rule it out. Also, no evidence of oil/coolant mixing, which suggests the oil cooler is OK. 

 

So I'm hoping it's just the back pressure from the heater matrix which caused the over flow, and silica impeding coolant pump 3; which I shall remove to check and clean out as best I can. 

 

But again, any advice and guidance with this would be most appreciated 🍻 

If you're handy with a spanner and happy to do so, why not remove the matrix and see if you can get any flow going?  I had some success with my Sister's Micra many years ago, with flushing back and forth, tapping and vibrating (chisel setting on a hammer drill - taking it easy as the core's not particularly robust) muck out:

 

 

Gaz

That cooler looks ok. I had white residue in mine. To check the charge cooler you can remove the temperature sensor and put a bore scope in. I got a cheap one off amazon and you could see the drops forming inside. 

Well it's been a while since I've had a chance to work on this due to the arrival of our daughter almost 4 weeks ago, but.... 

 

I have recently removed both electric pumps to check for flow and then refitted to run them with a flush. The rear motor, No.3 I believe, which had the intermittent fault of "stuck" logged, looked cleanest! Both seemed free and operational though... Bubbles in the front pump No. 2 had me wondering if someone else had tried a flush...

 

Just trying to find some suitable rubber hose to loop the heater matrix out at the moment, then I'll flush again thanks Gaz 👌 

 

T07, I had toyed with that idea, but first I think I'll try the chemical test again, once everything is flushed through, to see if any exhaust gasses are present 🤔 did you have any rough running from your leak, and did you put the system under pumped pressure to see the droplets? 

 

Keep the suggestions coming, thanks! 

Nope didn’t need to put it under pressure. There was no noticeable rough running to be fair. Just the lack of coolant!

6 hours ago, Whitie said:

Well it's been a while since I've had a chance to work on this due to the arrival of our daughter almost 4 weeks ago, but.... 

 

Congratulations on the new(ish) arrival! 👍

 

Gaz

Cheers Gaz, it's a whirlwind that's for sure! 

 

T07; I've not really had/used the car enough to notice any coolant loss before I started working on it. Could you say how far down the bottle was disappearing in a set amount of time/distance? 

Ta 

Maybe topping it up every couple of tanks of fuel. So what’s that every 800-900 miles or so?