Hi. I 1997 zx9r series c. The heat gauge is going

Chec fluid level or ucud hava leak. Buy a haynes repairbook for model at partstore. Umay also hav some air in radiator slowin down movement

The ac fan only comes on when the ac is on , the engine fan comes on at engine operating temp . few things to check , the radiator core fins are free from rubbish leave or plastic bags , the thermostat is fully open , radiator tubes are blocked with gunk have it flow tested .

more info what is wrong with it most Toyotas run half way up on temp gauge? do you have no heat? the heater assembly has 3 wires that break you need to remove it and take it apart and soilder it back together be carefull and tighten heat knob when done a new ones 800.00 iv seen them break a lot, you need a small pencil tip soilder tool mine butane works great.

The fuel tap is operated by a diaphragm being opened by vacuum. The pipe from the inlet manifold to the back of the tap may be partially crushed.
Pete

It will be a simple solution Paul it nearly ALWAYS is and usually a broken connection at the tank connector.

Check out related help links with solutions to troubleshoot the problem:---
Click the link below:---
2004 Toyota Tundra: Oil Gauge and Temp Gauge Not Working?

http://howtobyme.blogspot.in/2012/05/2004-toyota-tundra-oil-gauge-and-temp.html

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Toyota 4Runner: Temperature Gauge Sensor http://technoanswers.blogspot.in/2012/04/toyota-4runner-temperature-gauge-sensor.html

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http://technoanswers.blogspot.com/2012/01/heater-blows-intermittently-and-temp.html
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Heat blows cold on drivers side and hot on passenger side? http://schematicsdiagram.blogspot.com/2011/12/heat-blows-cold-on-drivers-side-and-hot.html

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1992 Lexus LS400: Engine overheats, Antifreeze out of reservoir and heater Blows Cold Air? http://whatisbyme.blogspot.in/2012/05/1992-lexus-ls400-engine-overheats.html

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These details will help.
Thanks.

If it is not an instrumentation problem then you have to assume the coolant is heat cycling. It could be because the cooling fans are not coming on due to the temperature switch, fans or relay. This would explain why the temperature increases when you are stopped and decreases when you are accelerating and air is moving over the radiator.

an air lock in the system.that is what the bleeders for...

Before getting too upset about this, try changing the temperature sender. Can't tell you where it is but it is usually on or near the thermostat housing but some engines have it on the intake manifold or rear of cyl head.

change the thermostat and the temp gauge in the radiator