Say, Skinnywater. Outside temp sensor on my ML430.

JB

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My '98 ML320 always gave an accurate outside temp indication. The '99 ML430 (Ol' Blue) is high, and goes crazy on hot days. . . 4 to 20 degrees high! It is particularly bad when driving slow.<br /><br />The book says that road or engine temp might drive it up some, because the sensor is mounted just behind the bumper. I wonder if it is misplaced or in contact with something it shouldn't be touching. <br /><br />Where, exactly, is the sensor mounted? Can I do something to get the accuracy the 320 gave me? Does it matter that the 320 was silver and the 430 is azure blue?
 

Skinnywater

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Re: Say, Skinnywater. Outside temp sensor on my ML430.

The ambient air temp sensors get dislodged all the time JB. And they read a little high if they're dislodged.<br />Look directly behind the bumper about 1 o'clock from straight forward of the left front tire. It'll probably be just hanging there. Look carefully from the front below and to the inside of the headlamp, in the air intake grille in the lower bumper section. You should see a round moulded hole the circumfrence of the sensor. It slides in there.<br />On occasion I've seen where a rock hits the very tip of the sensor damaging it as it does protrude slightly past the bumper. The very tip will be broken and will look like it has a hole in it. The new will have a closed point. <br />The sensor unplugs right at it and it's not very expensive.<br />My experience has been they're pretty dang accurate regardless of the color.<br /><br />Been replacing a lot of vibration dampers lately JB. The rubber in the front crank pulley goes away.<br />Keep an eye on it.
 

JB

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Re: Say, Skinnywater. Outside temp sensor on my ML430.

Found it, Skinnywater. Thanks.<br /><br />I think I caused the problem. I put a ML55 bumper grille in it and it must have disrupted the air flow.<br /><br />I will rig a deflector to get more fresh air directly on the sensor, which is not adrift.<br /><br />Thanks again. I will report results.
 

Skinnywater

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Re: Say, Skinnywater. Outside temp sensor on my ML430.

Time to powder paint the brake calipers red.<br /><br />The ML55 bumper has the same provision for the sensor JB.
 
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