"more expensive to replace the heater valve"
?????
The heater control valve in my 92 190E 2.6 cost $12 (US). And took about 20 minutes to replace.
Also, normal temp range is 82-107 celcius. Electric fan doesn't kick on until 107.
(Correct me if I'm wrong)
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'92' 190E 2.6
'89' Dakota Shelby
'96' Chrysler Sebring