Not an issue really but worth asking about. Normal idle speed is 700 RPM ...give or take.

Twice in the past month the 4.0 has idled high on cold start up. Idle hovers around 1000 & then once to 1800 RPM when revved.
A few key off restarts & it came right, it had a different idle RPM each restart though.

Throttle was "visibly" closed at idle, no vacuum leaks (rebuilt engine only has 90 thou k's on it), no difference when I touch/jiggle electrical plugs (TPS & cold start censor ), although revving it saw the revs increase & hold there ?!
Rather odd.

The engine has proven to be flawless & otherwise runs tighter than a Dutchmans wallet!

Anyone here ever had similar issues on the AU ?