InTTruder

1st: say "Q-dot = m-dot x delta T":
you are now a bony-fied thermal-hydraulics injunear!

Seems in stop-n-go (I've had this problem a while, and we've been trying to kill it) I can really heat up. Makes sense: less mass in the coolant inventory means more delta-T to get the heat out. Since outside air temp is 'constant', engine temp goes up.

This happened on International Boulevard: I needed 20 ounces of bottled water (damn near as expensive as G)! So, I drag it into the dealer (again) and say 'keep it until you fix it'. In 4 years of ownership this has been my only nigglin' problem.

Turns out to be the infamous o-ring, which we had already replaced at least twice. Don't know if it's technique, shelf-life, or just that damn crack pipe, but the o-ring was seeping enough to lose inventory. In long stop and go (but NOT steady highway scrambling) events, I eventually would steam off through the expansion tank cover. Frustrating. Around town, I'd top off (dammit) every 3K or so. On the road, not a problem. Oiy Vay!

So, keep an eye on yours, and head it off. AND I may get some Viton o-rings if I can find the right size!

Onward to the "Audi Over the Dragon" event in May! C-U there I hope!