Just had a run from the coast back home and on pulling out my local Sainsbury’s the thermostat went into red and warning on dash. Pulled over, managed to get the cap off and filled up with coolant. Not 5 mins down the road and it goes again.

Pulled over, stopped the engine. Lifted bonnet, came back and started engine. Back to normal. Started engine and within a minute back into red. Turn off and back on and back to normal. Start and a minute and goes red.

Any thoughts? Currently letting it cool back to cold so I might be ale to limp home.

Thanks

Tim

I assume you are loosing coolant ? so the first thing to do is find out where it's leaking from. 2012 TDV8 Vogue (L322)

Only from the expansion cap when it’s over heating.

Thermostat or waterpump failure would be the first suspects. 2012 TDV8 Vogue (L322)

Would either show up on GAP. Not seeing any failures that might point to cooling 😞. Water pump is less than 6 months old as well.

Neither will show on the gap as they are not equiped with sensors. If the waterpump is new ( Genuine?) then you are looking at the thermostat or some other coolant flow blockage. Why was the pump replaced BTW? Is it running smoothly and not throwing white steam out of the exhaust? Does it start smoothly in the morning. HC vapor test on the coolant would be a garage job to test for headgasket integrity. 2012 TDV8 Vogue (L322)

Let her cool down and attempted the one junction I needed to get down. Nearly made it 😞.

So, start the engine and she ticks over at about 700. After a minute, engine revs to about 1000 and temp goes above normal and then just starts to increase until red.

All in all, she got about a mile from cold driving as slow as I could before climbing to red line

Any idea on which one is the coolant pump fuse so I can check.
Thanks

So, resided myself to having to start looking for where the issue was since getting it home just about.

Went out this morning and while she was cold, topped her fluids up and I turned her around so the nose was pointing upwards (I have a slopped drive). I thought I would go for the easy option and see if she had an air bubble or something, so started her up and loosened the bleed screw on the expansion tank. She was drinking some fluids, so topped her up while running and.....

Well, temp got to normal and just sat there. Left her running for 30 mins, and still normal. tightened the screw, and took for a few spins around the block and she behaved.

Could this really be caused by something as simple as an air bubble. I am loathe to take on a long journey as it involves smart motorways and I was lucky I had some chevrons I could pull into yesterday but my normal trip I wont have that luxury.

Anyway, thought I'd let you know.

but I'd test it some more on local roads. 2012 TDV8 Vogue (L322)