2001 dodge Durango 5.9L magnum EFI with upgraded fuel injectors and Upgrade exhaust.

When the vehicle is in park it idles really high around 1500 any other gear with doesn't happen.
This isn't good because one of the people before me thought it would be cool to put a clutch plate in an automatic trans.

Also when I pull up to any stops in drive the vehicle will sputter and stall out and can be restarted right away but it's annoying.

So far I haven't checked much due to not having tools and being too stubborn to bring it to a shop and pay 400$ for a 50$ part.

 

Check your battery terminals for corrosion. Give them a good cleaning and see how it reacts then.

 

Check you vac lines for cracks / breaks. Iac may be clogged with carbon, Pull it out and clean it and the throttle body.