Why would this be a problem if the engine seems to start off a little higher than a new engine? It stays at idle at 700 rpms when warm the whole time after the engine is warmed up right? No check engine lights comes on, right? You need to be more descriptive for us to help you. Such as how does it run? Etc. Hpw many miles is this engine? Does it have temp spikes? Does it shut off?