help with dakota

Sounds like the clutch in the lockup converter is not releasing. Unplugging the harness going to the converter fixes this on a GM product.
A quick look at my parts book tells me you might want to be careful in unplugging the connector. If it has 3 wires it may also control the overdrive as well. It looks to be on the left hand side close to the valve body. Unplugging this may tell you if the solenoid is bad but I would only use this for diagnosis.