i have a 89 crx and like my temp gauge goes normal but after a while it rises up just under the h line then 10 sec later it goes back down to normal and 3 minutes later it does it all over again and one time i saw my car smoke when i stoped soo i poped the hoood and my radiator cap poped off half way..what do you think is wrong with my car

 

waterpump...

 

leaking waterpump. you're probably losing coolant at a small rate and sucking in some air.

 

yah but i asked someone and they were like it couldnt be your water pump because if your water pump was broken there would be water leaking and i dont see any water leaking

 

Next time you go out to start the car....pop the hood, make sure it is full of anti-freeze, leave the rad cap off. Start the car. After it is at normal operating temperature the anti-freeze should be flowing like a river. If it is not...its the water pump.

 

thermostat possibly... are ur fans working properly?

 

If the overheating is occurring while driving you likely have a blown HG. Double check your coolant level and make sure that your fans come on once the car gets to normal operating temp. The D15's had HG issues anyway and a Honda service bulletin was issued revising the HG and torque sequence. hth

 

thanks but i found out the problem i got a leak in the radiator a very small one soo after a while it got low and soo i filled it up all the way it hasnt done that crazy thing yet..

 

I have the same exact symptoms. The thing reads warm, then cold, then warm, and bounces all over (never to the red line though). And I am losing coolant when I checked my reservoir.

One thing though, isn't it dangerous to take that radiator cap off when the engine is running?