Temp Gauge Straight Up?

[JMI]

Have read on the forum many times that the temperature gauge indictor should be straight up in the 12 o'clock position. Anything other than that is abnormal. This can't be true in all circumstances though, during hot summer days, for example. Right?
At some point (<180 degrees?) the thermostat will be wide open with the fan running at full speed. At this point the only variable in the cooling system is the temperature and rate of flow of the cooling medium, i.e. the air passing through the radiator.
Yesterday the local temperature was 85+ degrees. My temperature gauge was at times hovering near the next gauge mark (the mark halfway between normal and the beginning of the "red" zone) depending on the engine load and the car speed. The higher temps were occurring in stop and go traffic but once I got going again the temp returned to "normal". Later in the day as things cooled off the temperature gauge had the reassuring straight up appearance.

Do others have a similar experience or is this something I should be concerned about?

TIA

Jim

[repenttokyo]

i wouldn't worry...if it's hot out, the guage is going to move.

[t_marat]

In here it can be more than 100F (40-45C) during the summer, and my temp gauge never went beyond halfway, always at 12 o'clock. And that is with a broken auxiliary fan.

[repenttokyo]

In here it can be more than 100F (40-45C) during the summer, and my temp gauge never went beyond halfway, always at 12 o'clock. And that is with a broken auxiliary fan.

are you sure your temp guage works properly?

i can't wait to add a real temp guage to the car that will give me water temperature in degrees.

[t_marat]

I had such fears. After all it was very hot, and the auxiliary fan was off. However, the temp gauge does work correctly. During the winter to make the engine heat up more quickly I inserted a cardboard bloackage (hard paper) between the radiator and front grill and forgot about it. Then in mid march on a highway I looked down on a temp gauge and was horrified, the temp needle was at about 13 o'clock. Thought something horrible happened, like a leak in the radiator. But then I remembered about that cardboard I put in there
Stopped and turned off the engine, removed that blockage, started again. The temp gauge was showing an even higher temp than when I stopped! Very close to the red zone! But then it cooled down quickly to its usual position. So this proves the temp gauge does work correctly.
When its very hot the fan clutch really engages. When you rev the engine it sound like a small turbine. Sound more like a big engine.

[zman-95-540i]

Here in Texas we have many days over 100 and my gauge never went past the middle mark last year.

[70383roadrunner]

Mine never goes above the 12 o'clock position regardless of temp outside and a/c running.

[Barney Paull-Edwards]

If the gauge does anything but point to 12 then something needs looking at, simple.

[whiskychaser]

If the gauge does anything but point to 12 then something needs looking at, simple.

Second that

[Ferret]

Second that

My old 525i used to be dead on 12 o'clock, but once I'd whapped the 2.0 head on it ran about 2-3mm over top dead centre...

If it's moving about like that your thermostats most likely duff.