Throffing in water header tank

[Ash-signum]

Hi all I come across a problem in my signum cdti 120 bhp.124k Miles.
i was cruising at 80mph and my water light come on dash so I pulled over to see that there was throffing in the header tank.the temp gauge had stayed the same like it always does and the water was warm as I could put my finger in it.there is no oil contamination there but am I right in thinking that there is possibly exhaust gasses mixing in there from the head leaking.
i turned the car on and of and drove another 20-30 miles no problem and stopped to check the water and everything was back to normal with no throffing and temperature staying the same.i haven’t lost no coolant and no pressuring either.
could it be rabies 😆
anyone had similar or no of anything.im doing the sniff test at weekend to see what is on but won’t bother if it’s head gasket.

[RBH]

https://www.google.es/amp/s/www.urba...ffing&amp=true

Really????

[Dog_Book]

Oh dear sounds ominous

[Ash-signum]

Frothing

[Teapot]

Most likely the EGR cooler has ruptured, allowing exhaust gasses into the cooling system. However if the coolant pump hasn't been changed lately it's well worth checking and replacing it (along with the timing belt), because it has been known for the impeller to come loose from the shaft.


If it turns out to be EGR cooler, choices are to fit a new EGR cooler, or fit a blanking plate at both ends of the EGR circuit and disable the EGR system in mapping.

[Ash-signum]

Still ongoing at the moment.it comes and goes.i have blanked the egr on one side.im getting no reading on the temp gauge.would this be a reason for it to be playing up?

[Ash-signum]

Think I may of solved it.you wouldn’t think it but after driving a 80
mile round trip I had no froth.i replaced the header tank cap thinking for the sake of £4 from
gsf what harm
can it do and it worked.it hasn’t lost no coolant either.im replacing water temp sensor to so fingers crossed it has cleared.

[fatfred]

Think I may of solved it.you wouldn’t think it but after driving a 80
mile round trip I had no froth.i replaced the header tank cap thinking for the sake of £4 from
gsf what harm
can it do and it worked.it hasn’t lost no coolant either.im replacing water temp sensor to so fingers crossed it has cleared.

Quite possibly the system was losing pressure hence the water boiling. Water under pressure boils at a higher temperature hence the reason for a pressurised cooling system.

[Dog_Book]

Quite possibly the system was losing pressure hence the water boiling. Water under pressure boils at a higher temperature hence the reason for a pressurised cooling system.

Physics

[Ash-signum]

The water didn’t boil.