well ever since i replaced my heads my car runs awsome until i drive in traffic or stop and go or just idling then the temp jumps up rather quickly and the performance goes down big time it seems to stutter when i step on it and feels like its losing power but if i let it cool down its runs perfect again, what could this be?

 

same with me dude, same exact thing, iu havent charged my a/c all the way yet so that could be it.
i replaced the thermostat and drained the radiator and it did help alot. but now im leaking coolant again from the lower radiator hoe and tonight it go hot again.
it just straight pisses me off badd! if you find an answern to yer prob let me know and ill do the same

 

\ill let you know, but i think it might be the ac cause in the proceess of taking my heads out i messed up the ac hose and have not replaced it yet ...wonder if thats it? i replaced the thermostat and drained the radiator as well....did not do tomuch

 

Take a read of the info at http://www.theherd.com/articles/lt1_cool.html the guy Scott Muller has some pretty good comments...it's a long article, but it is worth reading and understanding what your up against...

 

When the car overheats, do the fans come on? If not, you need to figure out why.