88 735i: Temp Gauge: Car getting cooler while driving

The temp gauge show car getting cooler while driving. I wait until the car is warmed before driving, resting in the center. While driving it starts going towards the blue.
Please let me know if it's something a mech needs to fix.
Thank you in advance for all the great solutions! I love this community!
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First step would be to replace the thermostat.
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*Suicidal twin kills sister by mistake.

Dave Plowman snipped-for-privacy@davenoise.co.uk London SW
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Agreed. Be sure to bleed the coolant properly afterwards!
Failing that the vicous coupling may have jammed so the fan is running all the time.
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Email: snipped-for-privacy@unixnerd.demon.co.uk, John G.Burns B.Eng, Bonny Scotland
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This is what cars do. When you drive, more air goes past the radiator.

If it's going too far out of range you can replace the thermostat, but if it's just a ten degree (of angle) difference, it's normal for any car. --scott
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in article snipped-for-privacy@f3g2000yqf.googlegroups.com, Chris Gloss at snipped-for-privacy@gmail.com wrote on 2/1/09 5:25 AM:

plan one ... temp guage is burning out from use and old age ... or your wires are that send the messages to the read out on the dash are losing impedence because of the heat. this suggests your engine is doing just fine and your electrical system is failing in this part of it. likely it is an easy fix, just swap out the temp sending unit.
plan two ... temp stuff is just fine .. and you are losing your thermostat, radiator works just fine in Arizona with 120 heat going on ... so it can cool things once it gets open. As it is likely open all the way all along, heating it up on idle gets it up ...running it in the wind brings it down ... rest on the road again with idle brings it up again. easy fix is swap out the thermostat ... can pull it and place it in a pot on the stove, heat the water up and watch it perform per specs if it is good.
if it is bad, when you pull it cold, instead of being closed, it will be in the open position.
sumbuddie hopes this helps
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