Morning guys just gone to drive to work started car then beep beep low coolant checked bottle was almost empty to got water undid the lid and coolant returned to the bottle, what would cause this any Ideas I'm thinking air lock some Ware??? 

 

2.0 tdi vrs on 07 

Edited 9 November, 20178 yr by bradh

Water returning to the bottle when undoing the cap would be due to a release of pressure...

 

How much coolant flowed back into the bottle? Was the engine dead cold?

Was running for 5 min then beeped at me and filled back up to just under min 

Just top it up about 150ml and it will be fine.

Do not use tap water! G13 only!

Edited 9 November, 20178 yr by Lyminton

The coolant in the system is incompressible and should not show volume variation beyond that of thermal effects. What you have experienced is compressible gas in the system which should not be there.

Although there are a few possible one off causes, if it happens again then it is likely to be an early sign of head gasket failure. Keep an eye on it.

Iv had another look now its light no sight of coolant anyware but there is a slight staining on the egr valve at the front Ware the exhaust gas is pumped into the valve possibly egr cooler fault? 

Could be the EGR. There are reports elsewhere of corrosion of the aluminium in the cooler causing leaks between coolant and exhaust gases.

Oooo I do hope so as it's cheaper to get it mapped and egr delete from darksidedevelopments.co.uk then new egr cooler 

 

Hopefully my picture uploads showing the coolant staining 

Had the same on mine. Airlock made the coolant level drop down to just above the pick up pipe on the header tank (car had been taken apart recently due to repair work so that's how the air got into the system) the coolant dropped, topped it up, been fine since. It passed a pressure test too so you could always get that done if you fancy an extra bit of reassurance

Mines not had any work done for a while now and that was replacing the water sensor flange on the passenger side of the block as the seal had failed, also did coolant flush at the same time but that was like 6 weeks ago I did that,  

On another (closed) forum there is a new report of soot in the coolant caused by a failed EGR cooler. As you have not reported soot then perhaps it makes EGR corrosion less likely.

The coolant gets foamy when releasing the pressure from the bottle but I just presume that's the watter just being over active when removing the bottle lid, it's booked in end of next week now for egr delete and map altered to suit so fingers crossed 

Ok spent the afternoon playing with the car running for 2 hours non stop looking for leaks squeezing pipes and it still pressures up a tad , but one thing I did notice is that after a drive heating is lovely and hot bang on 88 degrees on vcds then I stop at home and heating goes cool temp still at 90 on dash rev the engine and heating feels hot again let revs drop to idel goes cool again , what you think possible water pump issue ?? 

On ‎10‎/‎11‎/‎2017 at 18:20, bradh said:

Ok spent the afternoon playing with the car running for 2 hours non stop looking for leaks squeezing pipes and it still pressures up a tad , but one thing I did notice is that after a drive heating is lovely and hot bang on 88 degrees on vcds then I stop at home and heating goes cool temp still at 90 on dash rev the engine and heating feels hot again let revs drop to idel goes cool again , what you think possible water pump issue ?? 

 

Air/gases trapped in the heater matrix.  When idling the water pump does not force enough coolant in to clear it , when running hard the coolant is forced in and displaces the air/gas. The temp sensor does not get the temp. readings from the heater and shows the temp. from the engine. 

Leaking h/gasket or faulty EGR cooler can cause this. 

Quick update for you had the egr cooler deleted issues still there so trying to sort out head gasket replacement now :( 

Head gasket has been replaced and problems have been fixed gasket had failed between cylinder 2and 3 luckily iv got the later revived C code head so no cracks but still had it pressure checked just for piece of mind 

I've got a similar problem with mine, ive got a 57plate vrs pd170 diesel. A couple of months ago the bottom hose had to be replaced due to having a split in it then a month or so later the same happened to the top hose so replaced that aswel, since then we've had a problem with loss of coolant (which is going out the overflow due to too much pressure) vents only blowing out hot if the car is being driven or revved and car temperature going over 90 degrees and sometimes it's hit just under the red but the bottom hose never gets hot. I've now replaced the thermostat as the old 1 wasn't opening but still got the same problems but now with added foaming.  Car still drive's mint with no smoke or loss of power,

Sorry for the long message but I'm absolutely at a loss of what the problem is so hopefully someone will be able to help me out.

Thanks 

On 14/09/2018 at 23:20, Usx3 said:

I've got a similar problem with mine, ive got a 57plate vrs pd170 diesel. A couple of months ago the bottom hose had to be replaced due to having a split in it then a month or so later the same happened to the top hose so replaced that aswel, since then we've had a problem with loss of coolant (which is going out the overflow due to too much pressure) vents only blowing out hot if the car is being driven or revved and car temperature going over 90 degrees and sometimes it's hit just under the red but the bottom hose never gets hot. I've now replaced the thermostat as the old 1 wasn't opening but still got the same problems but now with added foaming.  Car still drive's mint with no smoke or loss of power,

Sorry for the long message but I'm absolutely at a loss of what the problem is so hopefully someone will be able to help me out.

Thanks 

 

If it’s foaming I’d be lookin at the head gasket failing and over pressuring the system, see if you can get a compression test done or someone to do a sniff test on your coolant for signs of oil