alrite, when i had my 93accord, it kept on doing this. when i'm warming up, the temp. gauge needle would increase slowly to the point where it's telling me it's warmed up. then, like 10minutes of driving it, the temp needle drops all the way down to 'cold.' then it goes back to normal. this SAME EXACT problem is happening to my b16a. but, when the needle drops, the engine act like it's cold and plays it out by warming up when it's already warmed up. i did replace the thermosensor on my accord, no workat that time! but it can be different with my b16a?!? anyone can help?

 

sounds like the thermostat in the engine is sticking, then when it gets hot enough, instead of opening up slowly like it should, it is "popping" wide open. this lets all the cold coolant in the radiator suddenly start circulating and this then shos up as cold on the gauge.... maybe.....

todd