1999 Mitsubishi Diamante • 176,000 miles

The diamante I own putters when I start driving and occasionally while I'm driving. It also idles really low to the point were it almost stalls out while I'm stopped. It also jumps when I come to a stop almost like it jumps into first gear when I'm slowing down around 20 mph. Any ideas.
March 25, 2013.

Sounds like 2 separate problems, For the low RPM you are equipt with a IAC (idle air control) motor, this is a stepper motor that make continuous changes. To maintain desired idle, If its worn it need to be replaced. Slowing down and the transmission jumps, Hows the reverse gear? Does the engine jump? Have the motor mounts look at, And also worn out transmission fluid can cause this sudden jump. So can a worn out transmission but that something else.

Mar 25, 2013.
If it doesn't say expert by name thenthese are not 2carpro people. Scan for codes and check fuel pressure first, clean throttle plate and iac hole with choke cleaenr if you have an iac engien has to run right prior to checking out transmission

Mar 25, 2013.