The past couple of days i've noticed that when i take it to the upper rpm range the temp gauge will peg to the cold mark, then when i shift it goes back to normal operating temp, same thing when i rev to the top of the next gear.

I have blead the coolant sytem a couple of times but no luck with that fixing it. I recently removed the IACV to clean it, i thought that might have let some air get in or something. I'm stupmed, tried searching but no luck finding anything.

 

https://honda-tech.com/zerothread?id=2003313

i have changed the thermostat and it seems to be working fine, i am also going to change the temp sending unit....

 

thanks for the link, its worth a try i guess. i'm pretty sure its not the sender.

Also let me add that it consistently does this, ie. every shift if i rev it high.

 

What procedure do you use to bleed the system? Sounds like you still may have air in there.

 

I would love to know what the problem with this is, as mine does the same exact thing.

 

i leave the cap off and crank the engine, let it reach full operating temp and let the fans kick on, top it off and put the cap back on. I think i forgot to slide the temp comtrol slider to the hot side though...dont know if that would make a difference here.

 

blead the coolant system again last night, the problem is still there but now the gauge only moves down 1/4 to 3/8's of an inch at high rpm's... getting closer lol.

 

found the cause, thermostat apparantley was getting ready to fail. I replaced it and it solved the problem. Hope this helps anyone that has the same problem inthe future.