When I drive my car LS 400 1990, it starts shaking (shivers ) time to time. If I am driving it uphill, all off sudden the car starts shaking, and feels like, Iam loosing power. The same thing happens when I stop at the signal. It shivers and comes back to normal ( Inotice hte RPM goes negligibly down while it is shivering). No engine lights are on. I checled up the car with local mechanic and they cleaned the fuel system, and nothing happened. The problem is still there. Iam not sure what is wrong with the car, please advice.
Thanks in Advance.