Idle problem...

[Simbolgades]

Okay, I searched and didn't find anything that describes my problem, so here goes:

Overall, the car runs and drives pretty well with no sputtering, hesitation, or bogging at all. Gas milage seems to be pretty good (around 22 city, 30 highway).

If I'm cruising along and I put the car in neutral and let it coast (like when I'm approaching a red light) the car idles nicely at 700-750 rpm UNITL the car slows to about 1 mph (maybe less) at which point the rpm shoots up to about 1200-1300. (Add about 200 to each number if the A/C is on.)

Just to make it more vexing, the problem is intermittant, and I haven't found anything that will immediately cause or cure it. It does this whether or not the A/C is on. The IACV valve (the one on the back of the intake manifold) has been replaced twice and the PAIR valve has been dismantled and the reeds thoroughly cleaned. Because the problem is intermittant, I'd suspect a leaky hose somewhere, but does anyone have any idea which one?

Like I said, this causes no real problem other than severe annoyance on my part.

Any help is appreciated,

chris'92 coupe

[TheOne]

check your thermostat, i heard a bad 1 can make the car idle in the !1000 rpm range