Mine has just over 160,000 miles.

After I replaced the injectors, it made a big difference in start-up, and it idles much better, but didn't actually fix the problem I was going after:

When I drive my car nicely (shift at 3500 or so) my car doesn't idle down and makes shifting a PITA because you have to slip the clutch when going into every gear. When it is cold this problem is non-existant, but as the engine warms up this condition progressively gets worse

However, when I drive it hard (shift at 5500 or so) it revs down normally and shifting is as smooth as it ever was, regardless of engine temp

I'm pretty stumped on this...