I'm currently on my third successive Golf since 1997, and have been delighted with the marque - both because it's exactly the car I need and because of quality/reliability and excellent service. I've had the current 1.9 turbo diesel since November. Yesterday was a very hot day, and I was in a queue of traffic trying to get to the south coast. For the first time ever on any of my Golfs, I noticed the temperature gauge was rising above 90° It went past 100° and was getting close to 110° and I started to get a little concerned. As a precaution, I turned off the air conditioner, and decided to take an alternate route to get out of the jam. Once I got some speed up, the temperature returned to 90° within about 2 minutes. I checked the owner's manual. A warning light is supposed to come on if the engine overheats, and there will be an audible signal. I didn't get those, but the temp gauge red line comes at 130°, and I wasn't close to that. The cooling fan WAS OK, but I will double check. Has anyone experienced rising engine temps as described here? This is my first ever diesel car, and I want to know if this is normal.