Engine hesitation

[Slessor]

I own a Holden rodeo 1989, 2.6 petrol
at low rpms it hesitates and once you get over about 2000 rpms it goes away and kind of slingshots you, I've changed plugs, and visually checked for vacuum leaks, and checked distributor cap and it had some corrosion, I've cleaned that up and reinstalled, cleaned the intake valve

Any help on what next

[tonkamu]

Should see if its throwing any fault codes