New tps installed its at .44 at idle . . all the way to the floor with the engine off its around 4.30 but going down the road at wot it only reads around 3.9 on my scantool . . its a 87 gn with only 16,000 miles on it . . is this normal or is there a problem . . what can i do to fix it . . also the car idles up to around 2000 rpm or so when in park and in netural for few seconds. . but doesnt do this when in gear and idles back down to normal after a few seconds. .is the iac bad . .any input would be helpful