The new temp. sensor (ECT) did the trick - cured all of the temp. gauge problems. My only current problem is a P0128 OBD check engine code. My research suggests that the problem is probably an aging thermostat. I'll ignore it for awhile and see what happens. I hope you're planning to recharge that A ...

Here's an update. While I wait for a replacement ECT (coolant temp.) sensor to arrive by mail, I have pulled the cooling fan fuse (it was running constantly) and disconnected the forward ECT sensor. Result? It starts and runs great . . . the temp. gauge climbs steadily to the half-way point - this ...

Thanks in advance for any thoughts.
This car has 150k miles and lives at 6000k feet.
Two problems that may be related:

1. Temp. gauge swings wildly on cold start. P0117 code. Suspect ECT sensor. Are there one or two ECT sensors on this car? I know the location of the first - by thermostat. If two ...