Honda Car Forum

I just recently changed my thermostat on my 1997 Honda Civic. About two thousand mile/ three weeks later the temp gauge shoots up the the H for about three miles then comes down as I pick up speed. I changed the thermostat and it does the same thing. THe car is not leaking water so I know the water pump didnt go out or that my radiator is broken. Could it be something as simple as the temparature sensor thats on the thermostat housing? THis is my work car and I need to fix it before monday comes around.and yes my fan is working.

make sure the electric fan is working. turn on your a/c, if the fan doesn't come on, the fan motor is bad or fan relay

For sure check the temp sending unit but otherwise if you have a good t-stat in your vehicle it sounds like you may have a leaking head gskt possibly caused by plugged radiator.

didi you replace or have it done at a shop? if you did it, did you bleed the rad.? then check your temp sensor ect. my integra did the same thing cuz i forgot to bleed it before i took it out for a spin

it could just be as simple as the sensor get it checked on the diagonstic at auto zone or something its free

Check to make sure that you are not getting compression gases in the coolant or coolant in the oil (which will make the oil milky). See if you are getting bubbling in the coolant overflow. If you are you may have a bad/leaky head gasket. Overheating an aluminum bloc engine is not a good thing as it tends to warp the head causing head gasket blowouts or leaks. you would usually know if you blew the gasket from all the billowing white smoke coming out the tail pipe. I don't know about the 97's but our '95 blew one and it was very costly to fix as there is a ton of labor to replace a $20 gasket because so many parts has to come off to get to the head on the 1.5 engine. Also, while you're in there you might as well change the water pump and timing belt - quick $1800 repair. Some Honda Civic's had a problem with the head gaskets and they redesigned the gasket to beef up the areas between the cylinders.Hopefully it is just a bad sensor. Did you bleed the system? there is a bleeder valve on my 95 Civic that is located where to top coolant hose enters the engine. It is a small 10mm bolt with a small hole on the top sitting on top of the part where the hose enters the engine. Loosen but do not remove the bolt while the engine is running until coolant comes out.