Idle RPMs and Carfax

[Matias]

Hi there!. After an 1800 mile trip (and a change in altitude from 5000 feet to sea level), I noticed that my car's idle RPMs went a little higer than they used to be (I estimate 700) and, the city MPG is now in the lower 10's (11.6 right now). Is this something that can be changed (the idle RPMs)? I should mention that it has a performance chip installed (love it!). Thanks!

PS...could someone please CARFAX this VIN for me? Thanks again! WBADE5329WBV95437

[peks]

hmm.. maybe a stomp test for starters?