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I was told that I need a new thermometer but my engine does not over heat, except occasionally when I run the air conditioner. I have also noticed my car sounds a little like a jet engine. Can you help?

Answers from the Automotive Experts

Amanda J. Pierce, MBA Joyce, Thank You for writing into AskPatty! You may be told that you need to replace your thermostat because of build up on or around it. Over time you can build up deposits which prohibit the true function of opening and closing. As for the sound, I am not sure how to pinpoint that, you may want to obtain a few different opinions. Hope this helps! A. J. Valle

Judy Curry, Co-Founder and Vice President of Marketing at Currys Auto Service Joyce, we recommend to have the fan clutch checked, it's electric on this model. If it's running full tilt all the time, it will eat gas mileage and make a huge noise. Bad thermostats are common on these motors and a good call if only for a just in case. A stuck open therm can cause overheats only when flow (RPM) is high and the fluid passes too quickly through the radiator to actually strip any heat off...if that makes sense. Stuck closed therms will overheat much more quickly. The primary test for stuck open is to use a graphing scanner to monitor engine temp during highway driving. A stuck open therm will lose heat at speed and gain it back when stopped. Hope this provides some insight! The Curry Team

Kerri Papajohn, Marketing Director at USA Sealants, Inc. A new thermostat is $15 - $20 and is a DIY project. Check on youtube and see if you can find a demo video if you need help installing it. I would replace it. It sounds like your thermostat's flap is stuck which causes overheating because it's open.

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