My dash dial always runs bang in the middle at 90 and the car seems to run just fine, only thing I could say is that I only seem to manage around 47-50mpg at best.
So like I say checked ch45, came up nice and quick but only to 75degs. remained nice and steady between 73 and 75.
So today I purchased a new genuine thermostate and seal from TPS (£25.20 all in) and changed it out.
I left the CTS as it was replaced just last year with a genuine item by the previouse owner.
Took her out for a test drive, quickly up to temp as before........90degs......result
little blast down the dual carriageway nice and steady 90-92degs.
Will have to report back on any improvements on MPG after a few days. I am led to believe that the ecu would have been slightly over fueling due to the low temp previously.