# Wrong reading on analog temperature gauge.cold start reads imediate 50 %gain on temp gauge

**URL:** <https://community.cartalk.com/t/wrong-reading-on-analog-temperature-gauge-cold-start-reads-imediate-50-gain-on-temp-gauge/40825>\
**Category:** Maintenance/Repairs\
**Tags:** mercury\
**Created:** [December 16, 2009, 1:03am UTC](https://community.cartalk.com/t/wrong-reading-on-analog-temperature-gauge-cold-start-reads-imediate-50-gain-on-temp-gauge/40825 "2009-12-16T01:03:20Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![johnk1202](https://avatars.discourse-cdn.com/v4/letter/j/90db22/32.png) [@johnk1202](https://community.cartalk.com/u/johnk1202)\
**Post date:** [December 16, 2009, 1:03am UTC](https://community.cartalk.com/t/wrong-reading-on-analog-temperature-gauge-cold-start-reads-imediate-50-gain-on-temp-gauge/40825/1 "2009-12-16T01:03:20Z")

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can you tell me the: senser that is bad and the loction on the engine.the car doesn t over heat or loose fluid.still provides heat.year 1995 4 door.

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**Author:** ![87\_Ranger](https://avatars.discourse-cdn.com/v4/letter/8/f14d63/32.png) [@87\_Ranger](https://community.cartalk.com/u/87_Ranger)\
**Post date:** [December 16, 2009, 2:54am UTC](https://community.cartalk.com/t/wrong-reading-on-analog-temperature-gauge-cold-start-reads-imediate-50-gain-on-temp-gauge/40825/2 "2009-12-16T02:54:18Z")

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The sender is most likely in the area where the upper radiator hose is attached to the engine.

Look for a single wire with a rubber boot & simply pull it off of the sender.

If the gauge now reads full cold replace the sender.

To simulate a hot engine shove a nail in the rubber boot & ground it to the engine. The gauge should now read full hot

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**Author:** ![mcparadise](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/mcparadise/32/32_2.png) [@mcparadise](https://community.cartalk.com/u/mcparadise)\
**Post date:** [December 16, 2009, 5:06am UTC](https://community.cartalk.com/t/wrong-reading-on-analog-temperature-gauge-cold-start-reads-imediate-50-gain-on-temp-gauge/40825/3 "2009-12-16T05:06:20Z")

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Please tell us the year of your Mercury.

Is it a Marquis, or a “Grand” Marquis?