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Discussion Starter #1
OK, so I am driving into work this morning and I was 20 miles into my 42 mile trip. It was cold out. 32F with a little sleet action happening. For some reason, I glance down at my water temp gauge and notice it is falling. It went from 190 all the way down like it hadn't even been running. It stayed at low temp for about 30 seconds and then climbed back up to 190 where it should be.
What could have caused this?
Is this an omen of bad things to come?
Nothing ran or sounded funny to make me look at the gauges, just happened to catch it.
Any info is always appreciated.
 

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Could be two things...

I've had a similar experience and it turned out to be my alternator. As the alternator was cutting in and out, the car would draw off the battery, draining it. As the battery drains, most of the electronics would cut out or dim out (on our cars there's alot of power hungry goodies). The alternator would then re-establish itself and things would come back up.

The other could be as simple as a wire loose.

Were any other items on the blink that you could tell?
 

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First change the $20 temp sensor. Cheapest and easiest attempt first.
 

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Discussion Starter #5
Were any other items on the blink that you could tell?
This was the only thing I noticed. I was listening to a cd, and nothing went funny with that. Was light enough out that I only had the DRLs on, so I couldn't notice if any of the lights dimmed. Gas gauge stayed put.

Thanks all for the input.
:bow:
 

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I'd say there is a 99.9% chance that this is faulty coolant temperature sensor. Do a search and you will find many threads that give instructions and information. This is a common failure of a cheap part ($5 to $15, depending on which one you have in your car), and can be a DIY repair if you are so inclined. Here is one recent thread that talks about this problem, but there are many more...

http://www.clubb5.com/forums/viewtopic.php?t=74425&highlight=

Cheers.
 
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