I have a 300D >The temperature reads 100c after its running in the summer heat.I checked to see if the plastic fan is working and it does not seem to be working.I found what looks like a temperture sender by the top hose (it has one wire ) is that the senser for the fan?Next to that is what looks like a sender with two vacume ports on it,One of the ports is plugged up. What is that for? Any info would help.

This subject has come up many, many times.

Do a search on "aux fans" and you'll learn everything you ever wanted to learn about how to diagnose this system.

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Steve
'93 400E

The fan is actuated by excessive high side pressure, not engine coolant temp. It is there to bring down high side pressure to prevent a/c system damage.

Have a great day,