If your EA888 is losing coolant and you can't find a wet hose, don't go chasing it round the engine bay — I already know where it is. It's the water pump and thermostat, and on this engine they're one plastic module that cracks and weeps as it heat-cycles. I've swapped more of these than I can count.
Here's what you'll notice:
- A sweet smell and a reservoir that keeps dropping, with drips down the back or side of the block where the module sits.
- The temp needle wandering — or swinging — as the thermostat sticks.
- A coolant warning on the dash.
What I do:
- I replace the whole pump/thermostat assembly — it's one unit, so there's no sense rebuilding a seal. And I only fit the revised module with the metal impeller and housing; the old plastic impeller erodes, and I'm not doing this job twice.
- I refill with proper G13 (it supersedes G12++) and I bleed it properly — trap air in an EA888 and it'll read as overheating when nothing's actually wrong.
I always do the pump and thermostat together — if one half's gone, the other's right behind it — and I check the hoses while I'm in there.
So: coolant loss with no hose leak on an EA888 is this module, near enough every time. Sort it before it cooks the alloy head — that's the bill you're really avoiding. See EA888 Timing Chain Tensioner and GTI Service Intervals.
For this job you'll want the revised metal-impeller pump/thermostat assembly and a fresh fill of G13 — I've put both below.