Staying between 80-90 on the gauge sounds normal to me for this engine. It's not uncommon for the reading to drop below 80 as well even when warmed up because it's partially measuring the return flow from the radiator.elma wrote:Having read what you said it probably is normal. It goes between 80 and 90 but not above. I'll hold on any thermostats. I'm used to s1 TDs which seem to sit in the middle.
What you'll find is if you can put a Lexia on it and monitor the ECU's temperature sensor during driving it will stay within a relatively small temperature range of about 87-93. Also if it was to go above 97 degrees the high fan speed would come on - if that was happening easily then maybe I'd worry, but I rarely if ever hear the high fan speed with normal driving, except when I had a bad connection to the brown sensor - after fixing that I haven't heard the high fan speed since.