I understand your logic. But if your idea is true then why is the rest of the black tube from the sensor to the motor black solid tubing.
Look at the picture above. The White tube is connected to two long black tubes.
The sensor is at the intake section of the tube. It is located at the center top of the dash. Just above the 2 outlets.
The tube goes along the inside of the dash, past the glove box and is connected to the "intake" section of the blower motor. The tube is designed to pull air over the sensor. The sensor is 1/2 an inch from the intake. So I don't see where the "temp" build up or cool down would effect the system temperature input.
1970 220D, owned 1980-1990
1980 240D, owned 1990-1992
1982 300TD, owned 1992-1993
1986 300SDL, owned 1993-2004
1999 E300, owned 1999-2003
1982 300TD, 213,880mi, owned since Nov 18, 1991- Aug 4, 2010 SOLD
1988 560SL, 100,000mi, owned since 1995
1965 Mustang Fastback Mileage Unknown(My sons)
1983 240D, 176,000mi (My daughers) owned since 2004
2007 Honda Accord EX-L I4 auto, the new daily driver
1985 300D 264,000mi Son's new daily driver.(sold)
2008 Hyundai Tiberon. Daughters new car