Subaru weird idle?

[CanonLaw]

I have never owned a subaru before, but i noticed at stop lights, when
the car is idleing, the engine sits at around 1000 for second or too,
then slowly drops down to 750 or so, then something clicks and it goes
back up to 1000 again, and this keeps repeating.

Is this just something Subarus do? I read another guys post saying his
2006 Impreza does this as well.
My car is a 2000 GT Wagon, 5-speed, 100,000 miles.

Thanks.

 

[thomashanno]

I have the same problem. My car (97 legacy outback) also seems to do
the same thing when I'm moving, usually coming from a stop.

People have suggested a few problems it could be: fuel injectors (I
tried a can of Techron), cylinder problem, and spark plugs (had them
replaced in February). Nothing has fixed it so far.

 

[strchild]

If your running the air conditioning or defroster, the AC compressor kicks
in on occaision for which the engine RPMs can spike a few hundred to
compensate.

May not be what you are observing though.

~Brian

 

[CanonLaw]

If your running the air conditioning or defroster, the AC compressor kicks
in on occaision for which the engine RPMs can spike a few hundred to
compensate.

May not be what you are observing though.

~Brian

Doesn't seem to be the A/C, as it does this when it is both on and off.
Also, I just had the cars wires and spark plugs replaced, as well as
the coil pack (don't know what a coil pack is) and thats when I noticed
it.

 

[Dmitriy]

Doesn't seem to be the A/C, as it does this when it is both on and off.
Also, I just had the cars wires and spark plugs replaced, as well as
the coil pack (don't know what a coil pack is) and thats when I noticed
it.

Make sure all the ignition stuff is plugged in all the way. May be a
loose wire somewhere.

 

[thomashanno]

Hmm....I sometimes can't turn my key and have to remove it / stick it
in again. These two could be related?

 

[Dmitriy]

No.

By ignition I mean spark plugs and associated wires.