i got a 97 grand cherokee thats havin issues when cold will idle in gear move 20ft a it will start idling low vibrate the whole jeep an die start it up give a lil gas drop in drive an it will go till u come to a stop then vibrates an diesbut as soon as put it will die as soon as tranny grabs no mater how much gas u give. it an when u drive down the road an shut overdrive off it wont come out of overdrive.anyone know what that could be