Engine Revs Up in Park after Long Drive

[Zardoz]

Hi everyone! I recently took delivery of a 1997 DB7 coupe (automatic), and I noticed after completing a few 30 mile drives that the engine revs up to 1500 rpm when I put it into Park in the garage. I tried quickly revving it up a bit more and then letting off the throttle to see if it was the choke, but it stayed at 1500rpm. I then shut it off and it stopped normally. It never does this after short trips around town, just the longer ones.
Anyone know what is causing this?
Thanks! Z.

[LMV600]

Idle speed control valve would be my first port of call .

[Zardoz]

Ok, thanks!

[oldboyswithtoys]

The throttle cables need setting up sounds like some one has adjusted them to tight

[oldboyswithtoys]

The throttle cables need setting up sounds like some one has adjusted them to tight