Hi, I have just got a similar problem. Check coolant came on computer, topped it up with 250ml of water but had a look around, the right hand plug shaft was full of clean coolant which i have siphoned out most of it but engine seems a bit lumpy. Could that be just wet around the plug causing it to be lumpy? Oil doesnt seem to be contaminated.
Is there a cooling chamber at the top of the engine that could have a gasket or leak without having to replace the head gasket?
I know the v6 had a some cooling around the plugs so hoping this has something similar.
Hoping this isnt the end for my baby..only done 81000 miles and owned it for 13 years.
Head gasket seems as if it would be costly.