Sounds like you either have a vacuum leak or the EGR valve
is hung open a little.

EGR on an idling engine or cold engine will make it act just like that.


1995 Trooper LS auto 3.2 DOHC /w SOHC intake
1989 Trooper 2.6 auto
1989 I-Mark RS DOHC 1.6
1991 Stylus XS DOHC 1.8