Hi all, my 91 200tdi is doing about 30 miles each way at the moment daily, i must admit, i like to check the levels frequently and rejoice in not having to worry, that week, about unexplained fluid loss, i was wondering why the water in the expansion tank only ever seems tepid, temp gauge hardly rises much, heater blower keeps me warm, is it because the engine is so not struggling or thats just the way it is.