# 2007 Volkswagen GLI - Thermostat?

**URL:** <https://community.cartalk.com/t/2007-volkswagen-gli-thermostat/167857>\
**Category:** Maintenance/Repairs\
**Tags:** volkswagen\
**Created:** [July 25, 2020, 4:51pm UTC](https://community.cartalk.com/t/2007-volkswagen-gli-thermostat/167857 "2020-07-25T16:51:29Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![EdD1](https://avatars.discourse-cdn.com/v4/letter/e/57b2e6/32.png) [@EdD1](https://community.cartalk.com/u/EdD1)\
**Post date:** [July 25, 2020, 4:51pm UTC](https://community.cartalk.com/t/2007-volkswagen-gli-thermostat/167857/1 "2020-07-25T16:51:29Z")

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engine light on, oil is fine, water temp is fine.  
diagnostic says thermostat needs replacement, but is functioning fine.  
Is there a temperature sensor  
that can be replaced without the thermostat?

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**Author:** ![Purebred](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/purebred/32/46796_2.png) [@Purebred](https://community.cartalk.com/u/Purebred)\
**Post date:** [July 25, 2020, 5:48pm UTC](https://community.cartalk.com/t/2007-volkswagen-gli-thermostat/167857/2 "2020-07-25T17:48:33Z")

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Google is your friend. Google engine temperature sending unit for your VW, bet there is a YouTube for it.  
How do you know the thermostat is working correctly?

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**Author:** ![Mustangman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/mustangman/32/44130_2.png) [@Mustangman](https://community.cartalk.com/u/Mustangman)\
**Post date:** [July 25, 2020, 11:32pm UTC](https://community.cartalk.com/t/2007-volkswagen-gli-thermostat/167857/3 "2020-07-25T23:32:51Z")

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What error codes exactly did the diagnostic find?

Yes you can replace the temp sensor without repalcing the thermostat by why would you? Both are cheap.

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**Author:** ![Tester](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/tester/32/15976_2.png) [@Tester](https://community.cartalk.com/u/Tester)\
**Post date:** [July 25, 2020, 11:37pm UTC](https://community.cartalk.com/t/2007-volkswagen-gli-thermostat/167857/4 "2020-07-25T23:37:24Z")

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If the code is P0128, the first thing that’s done is replace the thermostat.

> **[P0128 Coolant Temperature Below Thermostat Regulating Temperature](https://www.obd-codes.com/p0128)**
>
> How to quickly diagnose, repair, and info on symptoms and causes of a P0128 code which generally indicates a failed thermostat.

Tester