V50 General : Weird Intermittent Coolant issue

[TallPaul1975]

Good morning

We recently purchased our first ever volvo, a second hand 2010 V50 1.6Drive, since owning it, it's basically been fine to drive although we don't do too many miles per week, and very few long trips. But just the past few weeks we have had some weird behaviour from the coolant gauge, few examples:

Last weekend when it was really really hot, we drove to the next town seafront about 10 miles. Country roads there, left it parked up for most of the day and then drove motorway back. Coolant gauge stayed a nice and steady halfway (90 degrees).

Then a few weeks ago my partner did about the same distance to a town in the opposite direction, and straight back. On the way back she said she felt a lack of power, and the coolant gauge went up to just below the red for about a minute then came back down.

Yesterday we went on a trip 15 miles mostly over 50mph, left car parked for 2-3 hours while we went shopping, then drove back home another 15 miles, on the way there the car stayed at 90 degrees, but on the way back about 4 miles from home the car felt as though it had gone into limp mode, lack of power and needle on coolant gauge kept creeping up till finally the warning light and message came on dash to pull over switch off engine to allow to cool. We did for about 5 mins, then carried on driving were it kept going up to just below the red and back down.

We have also noticed that when we start the car almost straight away one of the fans come in - even with A/C off. And even after a short journey when we arrive back home and switch off engine the fans keep running on for a few minutes after.

Any advice, information and help will be greatly appreciated.
Regards
Paul

[Petey80]

Sounds like it could possibly be doing a DPF regeneration.

[FunkyMelon]

Sounds like it's overheated temporarily. After a night of sitting cold, release the coolant expansion header and see if there is any pressure.

If there is any pressure released, then you have gasses in the system and that'll most likely be a leak in the head gasket.

Get a hydrocarbon test done if this is the case as that will confirm.

[Bungo]

Originally Posted by Petey80

Sounds like it could possibly be doing a DPF regeneration.

I agree. Given the driving you're doing the dpf is not getting the chance to clean itself, also the fluid maybe low if it's a wet dpf for which you should get a warning on the dash.

However, regens do put up the temperature but not usually by that much unless it's proper blocked up.
Could be a few other causes and the best option is to get it plugged in for a diagnostic .

[Tannaton]

Sorry to be pessimistic but I suspect you almost certainly have a head gasket issue. Have you checked the coolant level? The next time it creeps up, try turning the heater to maximum and see if you get hot air from the vents - if not the you probably have an air lock in the system caused by low coolant level or combustion gases leaking into the coolant.

A DPF regen can greatly increase the under bonnet temperature but not the coolant to the degree you are saying. That said though it does also cause the fans to run on.

FunkyMelon’s tip is a spot on starter for ten....

[TallPaul1975]

Originally Posted by Tannaton

Sorry to be pessimistic but I suspect you almost certainly have a head gasket issue. Have you checked the coolant level? The next time it creeps up, try turning the heater to maximum and see if you get hot air from the vents - if not the you probably have an air lock in the system caused by low coolant level or combustion gases leaking into the coolant.

A DPF regen can greatly increase the under bonnet temperature but not the coolant to the degree you are saying. That said though it does also cause the fans to run on.

FunkyMelon’s tip is a spot on starter for ten....

I checked the coolant level and also run the car for about 10 mins or so without the cap on the expansion tank in case of any air locks to try and remove them.

When I switch the heating on and have it on hot it surely does blow hot air. I have also checked the oil level and for (slimy whitish sludge) indicating a blown head gasket. And likewise with the coolant when cold put my finger in it and felt if it felt oily, which it didn't. And doesn't appear to look as though any oil is in the coolant, through the colour etc.

Think will have to take it to the Volvo main dealers and get them to connect it to a diagnostic software. Hope they don't rip us off too much, I know they charge between £60 - £140 just to read it depending on what they find.

Recently ordered a Vida Dice of ebay but was one of those Chinese copies, finally got it to delete the airbag service issue message which was caused by me when I removed the passenger side dash panel to install my Nextbase dash cam cable to the fuse board.

When I did connect it, although I kept having problems trying to get it to connect to the car, when it did, it did show a huge list of faults. As I wasn't sure if they were old error codes or what I cleared them all.

I ended up returning the Chinese Vida Dice as it kept playing up, so haven't got it any more. And to buy a genuine one even second hand looking at near on £200.

Anyway thank you for all your comments and advice. Will keep you informed if I finally find out what is causing it.

A mechanic neighbour of mine who works for former KAP, said when I told him the problem that he would bet anything that it is the temp sensor, playing up on it's way out. And said to start by changing that, only with a genuine part as well as the cheap ones don't last or work properly.

[Tannaton]

Originally Posted by TallPaul1975

I checked the coolant level and also run the car for about 10 mins or so without the cap on the expansion tank in case of any air locks to try and remove them.

When I switch the heating on and have it on hot it surely does blow hot air. I have also checked the oil level and for (slimy whitish sludge) indicating a blown head gasket. And likewise with the coolant when cold put my finger in it and felt if it felt oily, which it didn't. And doesn't appear to look as though any oil is in the coolant, through the colour etc.

Think will have to take it to the Volvo main dealers and get them to connect it to a diagnostic software. Hope they don't rip us off too much, I know they charge between £60 - £140 just to read it depending on what they find.

Recently ordered a Vida Dice of ebay but was one of those Chinese copies, finally got it to delete the airbag service issue message which was caused by me when I removed the passenger side dash panel to install my Nextbase dash cam cable to the fuse board.

When I did connect it, although I kept having problems trying to get it to connect to the car, when it did, it did show a huge list of faults. As I wasn't sure if they were old error codes or what I cleared them all.

I ended up returning the Chinese Vida Dice as it kept playing up, so haven't got it any more. And to buy a genuine one even second hand looking at near on £200.

Anyway thank you for all your comments and advice. Will keep you informed if I finally find out what is causing it.

A mechanic neighbour of mine who works for former KAP, said when I told him the problem that he would bet anything that it is the temp sensor, playing up on it's way out. And said to start by changing that, only with a genuine part as well as the cheap ones don't last or work properly.

It's a shame you had problems with VIDA as that would have been a great help. On these engines it is usually a fairly catastrophic HG failure to cause water and oil to mix. The very early signs are small amounts of combustion gases getting into the coolant when the engine is under load.

The other thing it might be (which I forgot to mention) is a sticking thermostat - I have personally experienced this on my wife's V50 but the "wavering" of the temperature needle was limited to one mark on the gauge either side of normal. Cost about £20 in parts to fix.

If you have no other symptoms of a head gasket issue - I would get the thermostat changed.

The other option is the impeller coming loose on the water pump shaft but I have never heard of that on this engine before (used to be common on VW's with fibre-glass impellers).

[FunkyMelon]

I doubt it'll be the thermostat as they are designed to always fail open on these cars (engine runs cool rather than hot).

Did you notice any pressure or a slight hiss when you took the cap off the expansion header?

[TallPaul1975]

Originally Posted by FunkyMelon

I doubt it'll be the thermostat as they are designed to always fail open on these cars (engine runs cool rather than hot).

Did you notice any pressure or a slight hiss when you took the cap off the expansion header?

Hi thank you for your comments, I have to be honest I've not got round to checking it when it's been left cold for a while. Will do it asap and let you know. I have a brand new thermostat here which I ordered a couple of weeks ago, but like you I felt it wasn't properly the thermostat as this wouldn't be an intermittent problem, it would either always be running hot or cold (as you said)

I have just ordered a head gasket gases test kit from ebay and give that a try to see what the results are. They have sold hundreds of these kits with 100% positive feedback.

[TallPaul1975]

Well been out and removed the expansion tank cap when cool, and there was a small release of pressure, but I was led to believe that all coolant systems work under pressure and a certain amount of pressure is normal.

I then started the engine with cap removed and left running for about 10 mins or so and kept an eye on the expansion tank for any sign of air bubbles (Gases) rising to the surface, also revved it a few times and still nothing. No bubbles.

So now left thinking it is most probably the temperature sensor, or a more serious problem with the ECU or management system. So will have to get connected to a computer and diagnosed.