DS7 identifying noise from engine.

[Nmullan54]

I own a DS7 2018 2.0 BlueHDI engine the better half uses the vehicle 99% of the time for work.

Short version:

Please see attached and let me know what you thoughts are on the noise,



Engine was on for approx 20seconds heard the noise and switched it off. With below I was questioning water pump. However, the noise seems to be coming from top/ passenger side of the block and if I am correct water pump would be opposite side of the engine. The sound seemed to come and go in that time few seconds on few seconds off.

Any help would be appreciated.

It will be going to a mechanics but at the moment she’s stranded on the drive and the mechanics is no where near us.


Long context of the issue

To be honest it’s been endless trouble. I’ll give a little background to this one,

The latest issue appeared the other evening, driving down the road alert threw up engine temp stop vehicle now, I pulled over and checked and found the Coolant cap on the top of the engine cover, now the other half had added coolant to the car a day or two before while I was at work. I doubt she would have left it off but at that time I thought it was possible.

Any stopped the car at road side and let it cool down, coolant had boiled over engine bay full off coolant and there was little coolant left, the engine was let cool down and refilled with coolant. Idled the engine and tried to burp the system to remove air possibly trapped. Traveled the short distance home no issues checked the coolant level and also engine temp and coolant temp with Onboard meters on the dash. No further warnings either.

Car was taken out the next day and fired up an amber engine needs repair warning light, again I had both engine and coolant temps on the personalised dash and both were settled at the 90degree mark, no over heat warning this time,
Car was taken back home, on opening the bonnet engine coolant was visibly boiling in the reservoir. And engine has a small amount of steam coming from the block area.


She’s been parked in the driveway since, I thought it may have been trapped air in the coolant system due to the overheating and road side refill and burning attempt.


I’ve removed and flushed the coolant system which had viable crude in it little black marks, I flushed it with fresh water until clear and got some engine coolant system cleaner to help remove any other deposits.

I switched on the car and was going to check the coolant was running through the reservoir while hoping to bring it up to temp and idle the cleaner through the coolant system. And was immediately greeted with the second noise in the video above.
Switched her back off.


Oil is clean so don’t believe coolant is reaching oil.


Thank you

[myglaren]

You need to make the video public viewable.

[Nmullan54]

Yep that would help Should be sorted now.

[PaulC5]

No idea what the noise is but from your description it appears the head gasket has failed, possibly when the coolant cap was left off and the coolant boiled out so the engine overheated. The cylinder head might also be warped due to overheating. You can get cheap test kits to check for combustion gases in the coolant tank so could be a first step but you appear to already have the gasket leaking externally from the block area. If you continue to run the engine any damage may get worse and more expensive to fix.

[Nmullan54]

Thanks for the reply. Don’t think I would risk running her again. I’ll just have to sort out recovery.

Is there a possibility the second noise could be a failed/ failing high pressure pump? I know it would be in the vicinity of where it sounded like the noise was coming from.

To be fair I don’t believe the cap was left off, however I can’t 100% rule it out, I was informed it certainly wasn’t and it would be very unlike her.

The oil is clean when checked and is in good condition, would the head gasket blown not show in the oil with the dreaded milkshake? More for my own interest

She’s already had a water pump replaced for something similar a year into owning her, in fact while under warranty DS have spent approx £15000 on repair costs before the 2 years warranty ran out, ( often with a lot of arguing) along side a substantial car hire bill they covered for the months she was with them.

I think this will finally be the end of my Love hate relationship.

Cheers

[PaulC5]

Our coolant expansion tank caps have all screwed on so if yours is similar it would seem odd for it to self unscrew and then fly off to land on the engine cover. Oil pressure is higher than the coolant, especially with the cap off so if the coolant/oilway paths in the head gasket fail then oil is more likely to end up in the coolant and not the other way round.

I did wonder if the buzzing noise is the egr valve trying to do something.

[Nmullan54]

A okay, the coolant itself looked clean when I drained and flushed the system, although in the reservoir there was a residue, almost gritty, which I am guessing is minerals or residue left from the boiled of liquid. I remember when the Water pump failed previously when DS themselves recovered her the coolant reservoir had exactly the same residue.

Mmm your may be on to something with the EGR valve just had a nosey at a few videos on YouTube of failed EGR valves and the sound would be a similar!

Any knowledge of a failed EGR valve of issues with it would show up on Diagnostic?