Overheating ??

[freddyuk]

Car has had issues since towbar fitting as not fully coded. Collected car and driving home overtemp warning came up. Engine did not seem hot but after stopping for a few minutes it went back to 90c  and no further problem for weeks. Then it happened again and quickly went back to normal. I put this down to sensor issue. We then loaded up trailer and towing to France and quickly the gauge went up to the red. Once alarm goes off the car goes into limp I think.

After stopping it went back to 9i0c and stayed there for the rest of the trip to the ferry about 1 hour drive.

In France same problem. Nursed the car along motorway as hills put temp up and we coasted down them to cool down. Then for 200 miles it was rock solid at 90c. ??

Then suddenly went up for no reason and message "add coolant". I could see the reservoir was still full. When I released the cap the water ejecterd from the reservoir via a valve on the side and mostly emptied. I refilled and set off again. The gauge eventually stabilised and we got to our B&B.

Next day no trailer attached so we thought no problem but within a mile temp went up again. Stopped to cool down. I noticed the radiator hose was cold.?? water still full. We carried on and nursed to destination. Then after long cool down we drove with heater on full blast 28c to help cooling. The air was warm/cool/warm but not hot.

The after getting too hot again the air was blowing cold no heat at all. The rdaitod=r hose was still cold and the pipe from reservoir just warm.

Engine is too hot to touch but radiator seems cold so I think thermostat not opening. But on way back  home strangely got hot quickly and then after crawling behind a tractor it dropped quickly to 90c. I thern drove brskly for several miles and it stayed at 90c no problem but then did it again. After slowing down it cooled back to normal quickly aND i drove briskly home with no problem (lots of hills).

Got out and both fans were roaring away. Reservoir still full. Switched off igniton and one fan switched off and one kept going for  5-10 minutes. Checked radiator hose and still stone cold.

 

What do you guys think please?

[J.R.]

Water pump impellor shroud sticking.

 

For temporary relief remove the electrical connector when the engine is at normal operating temperature and not overheating, that is to say when it is behaving, you could do it later after the engine has cooled as long as it was behaving correctly on the previous run and you dont turn on the ignition again until after the connector is removed.

 

You could just leave it like that and it will be fine, in winter you will notice a slightly increased warm up time and a little longer for hot air to come from the heater, many fit a water pump without the shroud which gives the same effect.

 

Rest assured it is nothing to do with the towbar fitment.

[ApertureS]

It sounds like the classic water pump shroud seizing.

 

you’ll need a timing belt and water pump replacing if it found to be that. But the symptoms you describe all match up.

 

the reason it happens under load is the engine is fairly good at self regulating it’s own temperature without any flow needed at low load and revs, whereas at higher loads it needs the water pump to assist with moving the coolant a bit faster to cool the engine a bit. There is a metal sleeve over the water pump that moves up and down to regulate coolant flow and this seizes in the open or (mainly) closed position 
 

also - don’t open the coolant cap on a hot car!!! You risk 100+ degree water exploding out the reservoir all over you.

 

[freddyuk]

I knew you guys would know so thanks. It is a holiday here so no chance of any garage services until later next week. Can I free up this shroud somehow or just do the connector disconnect option. Not sure where the pump is but guess front of the engine - follow the water pipes?

It is probably due for timing belt kit but we need it for 2 weeks until we get home.

I am aware of the reservoir cap issue and was very careful but as it is screw cap I can slowly undo and ensure no massive pressure loss. In fact the first time I took it off there was no pressure I guessed the cap was already loose and therefore low warter pressure was causing the problem but after tightening the cap it still happened so was not this.

Really appreciate the instant response as we stuck here without a car.

 

[freddyuk]

1 hour ago, J.R. said:

Water pump impellor shroud sticking.

 

For temporary relief remove the electrical connector when the engine is at normal operating temperature and not overheating, that is to say when it is behaving, you could do it later after the engine has cooled as long as it was behaving correctly on the previous run and you dont turn on the ignition again until after the connector is removed.

 

You could just leave it like that and it will be fine, in winter you will notice a slightly increased warm up time and a little longer for hot air to come from the heater, many fit a water pump without the shroud which gives the same effect.

 

Rest assured it is nothing to do with the towbar fitment.

I am just checking which connector ? Is it on the reservoir or the engine?  Thank you

[freddyuk]

On 19/05/2023 at 17:44, J.R. said:

Water pump impellor shroud sticking.

 

For temporary relief remove the electrical connector when the engine is at normal operating temperature and not overheating, that is to say when it is behaving, you could do it later after the engine has cooled as long as it was behaving correctly on the previous run and you dont turn on the ignition again until after the connector is removed.

 

You could just leave it like that and it will be fine, in winter you will notice a slightly increased warm up time and a little longer for hot air to come from the heater, many fit a water pump without the shroud which gives the same effect.

 

Rest assured it is nothing to do with the towbar fitment.

I have figured out how this would be a solution as I now understand what is going on. We are desperately trying to get the gauge to drop to 90c so we can pull the plug but it is refusing to do it now. It was before we knew the trick. I hope it is not jammed now so will keep trying as repair kits are all out of stock in France. I just need it to open and then disconnect. I guess it does not matter if the engine is running or not when I disconnect the solenoid so long as the shroud is "off"? 

[J.R.]

Correct, its worth giving it a try when cold before turning on the ignition, it may have retracted during the night.

 

Water pumps will be available in France but nobody wants to do any work, order anything or commit to anything in the month of May, there are so many bank holidays where people faire le pont (not work the remaining days after a public holiday) that effectively its a month where nothing happens, next day deliveries take 4 weeks.

 

Even when people have to work they will attend but do nothing, of course most of them are still (not) working from home.

[freddyuk]

Oh great! We are staying with an English couple B&B and they have been great offering a car etc. and we have a garage available for the work next week if I can get the kit. It is an English guy who owns the garage. Not really integrating but we have to be mobile asap.

I ordered a kit online from an independent seller and find out after paying it is an order going to Autodoc who I already know do not have stock of the kit. So tomorrow I will find out if it is going to be a cancelled order.

The car was overheating when I got back today so it will be in closed position. Will try again tomorrow.

[freddyuk]

I am thinking here (on a Sunday) of a solution to release the stuck shroud. If the engine is hot and the shroud is being pressurised by the solenoid piston to open the shroud - with engine off and cable disconnected could you use something to vibrate the water pump shaft end to maybe release the shroud enough to get flow??  Just an idea. Mine has only just stuck so may be freed off with a bit of tapping or even a gentle hammer drill action on any part of the pump which is accessible -  which may be a problem.???  It all looks very tight and I am not sure if any part of the pump body is actually visible from above or below.

I know, clutching at straws here......

 

[J.R.]

It is not pressurised or actuated by a solenoid piston its the water pressure from the pump that moves the actuator against the return spring, the solenoid allows the water to flow to the actuator.

 

As it should return under spring pressure giving it the good news with a hammer & drift may release it, it depends how crudded up it is.

 

When you order anything over the counter from a motor parts shop if you walk behind the counter to see what they are trying to hide from you on their computer screen you will see that they are ordering from Autodoc and putting their margin on top of the price you could pay yourself.

 

Nothing arrives during May anyway.

 

Editted, I meant Oscaro and not Autodoc, perhaps you should try them?

Edited 22 May, 2023 by J.R.

[SuperbTWM]

Although I agree that it does sound like classic failure of the water pump shroud there are 2 things that don't quite add up:

 

The heater matrix loop uses an electric pump to circulate so if there was a problem with the main pump you would get heat in the cabin regardless, maybe this pump has failed or is this a more siniser fault like a blockage?

 

and even with very poor coolant flow, with the amount of heat in an overheating engine the thermostat should still open and allow some water into the rad so I would expect the top hose to be hot, the bottom one however may be stone cold, which hose were you feeling? could the thermostat be blocked?

 

Silica teabag maybe?

[freddyuk]

The top hose was cold and the hose from the reservoir was cold. I did not crawl underneath as I was out in a car park. When we went out yesterday to try and release the shroud by driving the air was warming up from the vents as normal as you would expect. I then shut off the heater as I was trying to get to 90c asap to see if it held there or kept on going up - it kept going up. I drove at crawling pace to get it back to 90c and hoped it would trigger the shroud but it refused to drop far enough. If I stopped it would go down to 90c and stay there but as soon as we started up it would go up on the first incline.

Before that the other day when I was trying to cool it down I had the heater on full 28c and it was blowing warm - then cooler - then warmer but finally it was stone cold.

 

I have heard about these bags in the reservoir but have not investigated. I see it is advised to remove them.? If I can see it I should remove it. If I cannot see it is it in the system somewhere?

 

I noted JR you are in France so know what you are talking about. If I cannot get a kit here I am thinking get the local garage to remove the pump - release or just cut off the metal shroud and replace it to get me home.

 

I will look for this teabag now........

 

It just occurs to me that there is no thermostat on the engine that is what the shroud does on the pump??

Edited 22 May, 2023 by freddyuk

[J.R.]

There is a thermostat, removing it may help alleviate the sleeve problem.

 

Did you remove the connector when the engine was cold before your test ride?

[J.R.]

I editted my previous posting:

 

Editted, I meant Oscaro and not Autodoc, perhaps you should try them?

[freddyuk]

We got to Limoges yesterday by driving at 40mph and stopping to let traffic past. Crawling up hills and coasting down. We managed to keep the alarm from going off but it did get to the red sometimes. OK to drive very slowly around town. We collected a kit from Skoda dealer at double the normal price. They could fit in in July!!

Going home we nursed car along but going out of Limoges the gauge started drop back to 90c and stayed there even up a hill so I pulled over and prepared to pull the plug. A car pulled up behind us and it was another Irish car who wanted help us if we were lost! I left the car running and the temp was at 90c when I discoonected the solenoid feed. Aftet that it did briefly go up to 120c but quickly dropped back to 90c and stayed there until we got home about 20 minutes later.It seemed to drive normally for the rest of the trip back.  I do not know if the shroud retracted on its own or pulling the plug had an effect..

I will find out today if it has reverted to being stuck or if we have some circulation. The heater was blowing warm when we set off but went cold again. It stayed cold all day.

The car is booked in with a local garage hopefully tonight.

[SuperbTWM]

Good luck with the repair, and let us know how it goes, hopefully it's as simple as the water pump!

 

[J.R.]

I drove past Limoges on the way back yesterday, if you are 20 minutes South then you are probably not a long way from me if I can help in any way.

 

I have VCDS.

[J.R.]

On 23/05/2023 at 07:10, freddyuk said:

The heater was blowing warm when we set off but went cold again. It stayed cold all day.

 

That does not sound encouraging, there is normally a seperate electrical pump for the heater.

 

The guage going up to 120° I can explain, you probably know that the readings are fiddled for the needle to read bang on 90°c over a wide range, when it moves it moves a long way!

 

When you stopped to remove the connector the engine was probably over 90°, there would then have been heat soak while the engine was not running, I can understand it going up to 120°c quickly but if it dropped down again quickly then the water pump is now circulating.

 

I am a bit concerned about the cold heater though, that sounds like a Silkat blockage, have you looked in the reservoir and at the colour of the coolant?

[freddyuk]

Sorry for the delay. We had no internet. Waiting for Orange Fr.  to flick a switch - some hope.....I am now on my Hotspot - a big bill will be on the way.

The car went in and timing kit was fitted with pump. Cost was 225 euro for the fitting. Drove back yesterday and no overheat. Had the Aircon on as it has finally turned very warm here. Stopped at the supermarket. When we restarted I had a check engine light on so this is not over yet.

I checked the water reservoir and there is a bag in there but looks undamaged and no signs of debris. The water is pink and within the level marker.

I did not test the heater as it was very warm but can test today.

I have the usual threat from the Adblu message to buy some Adblu of your car will die - I love being bullied by a car. This should not cause engine fault.

BTW I am up in Creuse near Gueret about an hour from Limoges. Will be going down to Julliac some time next week.

 

All comments gratefully received.

 

 

 

[SuperbTWM]

How many miles remaining on the Adblue? Not sure if this could bring EML on to put extra pressure on you to refill if it gets very low, the car will not start wonce Adblue is empty

 

You really need some diagnostics to further identify the issues. Have you used the car on a few more trips to confirm your overheating issue has definetly gone?

[freddyuk]

Went out today and no issues with water. I spoke to the guy who replaced pump and he confirmed it was jammed closed. He was very interested in the problem.

 

I put in more Adblu until it was full. Still stuck at 800km left. I started a new thread on this problem.

I called Skoda in Ireland and they suggested I should claim on my insurance!! Wonderful service.

I am going back to the same garage tomorrow and he has a scanner but it is only valid software up to 2014 so may not have any effect on my car.??

 

 

 

[PhilMorand]

I have the same problem is FreddyUK originally described.  Hopefully it's 'simply' the water pump shroud sticking - any advice on whereabouts the connector to disconnect is please?  BTW, I've run VCDS diagnostics and nothing shows up other than the distance warning module incorrectly coded (following the fitment of a towbar).  Any thoughts?  TIA.