I have a 4HP22 gearbox, with a kick down cable on my '89 535. For about a month it would not change gears unless it has warmed up. If I warm it for about 5-10mins it will take off well shifting normally. If I don't I have to crawl in the 1st gear for a while, revving up to 4500rpm before it changes to the 2nd. What do I do?