# Weird Car Problem

**URL:** <https://boards.straightdope.com/t/weird-car-problem/734758>\
**Category:** Miscellaneous and Personal Stuff I Must Share\
**Created:** [October 15, 2015, 10:13pm UTC](https://boards.straightdope.com/t/weird-car-problem/734758 "2015-10-15T22:13:41Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![ralph124c](https://avatars.discourse-cdn.com/v4/letter/r/8797f3/32.png) [@ralph124c](https://boards.straightdope.com/u/ralph124c)\
**Post date:** [October 15, 2015, 10:13pm UTC](https://boards.straightdope.com/t/weird-car-problem/734758/1 "2015-10-15T22:13:41Z")

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Just last week, my check engine light went on. I pulled out my code reader, and plugged in-it read p0128 (coolant temperature too low). I checked everything, and the heater works fine.I bought a new thermostat, since i read that this code usually means a stuck-open thermostat. Next, today, the low coolant lamp lit up\_ I checked the reservoir, and it was down a slight amount-I added about 5 ounces of coolant, and started the engine-both lights went out. I cannot detect any leaks, and there is no indication of any internal leaks-what could it be?

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**Author:** ![gotpasswords](https://avatars.discourse-cdn.com/v4/letter/g/c57346/32.png) [@gotpasswords](https://boards.straightdope.com/u/gotpasswords)\
**Post date:** [October 15, 2015, 10:41pm UTC](https://boards.straightdope.com/t/weird-car-problem/734758/2 "2015-10-15T22:41:00Z")

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Is it still complaining of low coolant temp? The sensor itself may be failing. Unless you topped off the coolant the day before, I wouldn’t worry excessively about being down a half cup. Actually, on re-read, you probably had an air bubble in after putting the new thermostat in, and once it got “burped” you were down 5 ounces.

Otherwise, what kind of car is this?

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**Author:** ![ralph124c](https://avatars.discourse-cdn.com/v4/letter/r/8797f3/32.png) [@ralph124c](https://boards.straightdope.com/u/ralph124c)\
**Post date:** [October 15, 2015, 11:38pm UTC](https://boards.straightdope.com/t/weird-car-problem/734758/3 "2015-10-15T23:38:41Z")

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It is a 2002 Saturn SL1, with 85,000 miles. The check engine light has gone out.

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**Author:** ![Gatopescado](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gatopescado/32/5711_2.png) [@Gatopescado](https://boards.straightdope.com/u/Gatopescado)\
**Post date:** [October 16, 2015, 12:13am UTC](https://boards.straightdope.com/t/weird-car-problem/734758/4 "2015-10-16T00:13:12Z")

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Sounds to me like a weird car un-problem. Drive on!

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**Author:** ![WildBlueYonder](https://avatars.discourse-cdn.com/v4/letter/w/ce7236/32.png) [@WildBlueYonder](https://boards.straightdope.com/u/WildBlueYonder)\
**Post date:** [October 16, 2015, 12:18pm UTC](https://boards.straightdope.com/t/weird-car-problem/734758/5 "2015-10-16T12:18:01Z")

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> [@ralph124c](#):
>
> It is a 2002 Saturn SL1, with 85,000 miles. The check engine light has gone out.

burned out! 😛