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The car (e85 3.0 ) spits coolant through the radiator cap when the engine is hot and only while driving the car ( doesn’t when I let the car sit and get up to temp )
I replaced the thermostat and still the same thing is happening again, also it doesn’t show any sign of a bad or blown head gasket.
Anyone had this happen or know what causes this to happen ?
All help appreciated
Thanks in advance

Try a new cap
Rob

I have a rad almost new tank and new hoses for sale. But as said just try a new cap first

Sorry forgot to mention I tried new cap first since it was the easiest option

Could be a split (crack) in the expansion tank near the cap? So looks like it’s the cap... but could be the threaded section?