My van started stalling while riding down the road. At first it was only stalling after about 15 miles. This morning it stalled before I left my street. It usually will start back up, but sometimes takes 4 or 5 times to get going again. It runs fine when it runs, but when it cuts off the speedometer and oil pressure quit reading but we still have power and readings on evrything else. It doesn't seem to matter if you are slowing down or accelerating. Any advice?