# 06 ranger thermostat trouble **URL:** \ **Category:** Maintenance/Repairs\ **Tags:** ford, ranger\ **Created:** [May 25, 2010, 12:20pm UTC](https://community.cartalk.com/t/06-ranger-thermostat-trouble/49357 "2010-05-25T12:20:30Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![mattman](https://avatars.discourse-cdn.com/v4/letter/m/e47774/32.png) [@mattman](https://community.cartalk.com/u/mattman)\ **Post date:** [May 25, 2010, 12:20pm UTC](https://community.cartalk.com/t/06-ranger-thermostat-trouble/49357/1 "2010-05-25T12:20:30Z")
I just bought a used 06 ranger sport. It runs fine, but during the first 5 minutes of driving the thermostat will act funny. It can shoot from cold to very hot within 30 seconds. It will stay there for a minute or two, then within seconds it will drop to normal. It may go up again, but after a few minutes it does not go up again. Has anyone ever run into this? ---
**Author:** ![common-sense-answer](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/common-sense-answer/32/716_2.png) [@common-sense-answer](https://community.cartalk.com/u/common-sense-answer)\ **Post date:** [May 25, 2010, 12:35pm UTC](https://community.cartalk.com/t/06-ranger-thermostat-trouble/49357/2 "2010-05-25T12:35:16Z")
Don’t Guess. Get The Truck Checked Immediately. It Could Be A Faulty Sender Or Gauge, But Sounds More Like Air In The Cooling System And You’ll Damage Your Engine. CSA ---
**Author:** ![common-sense-answer](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/common-sense-answer/32/716_2.png) [@common-sense-answer](https://community.cartalk.com/u/common-sense-answer)\ **Post date:** [May 25, 2010, 12:39pm UTC](https://community.cartalk.com/t/06-ranger-thermostat-trouble/49357/3 "2010-05-25T12:39:33Z")
With The Vehicle Cold, Has Anyone checked the coolant level in the coolant reservoir and radiator (if it has a cap) ? The radiator should be full and the reservoir shouldn’t be empty. CSA