Hello, during a test drive with a Saab 900-II Turbo 136kW started knocking after 100km while accelerating the engine. As it turned out with the subsequent control of the oil level, this was below the MIN mark. Even after the oil refill, the engine still makes SINGLE noises. In the stationary gas the noises are not heard. If you increase the speed, the knocking and/or hitting becomes inaudible. Now the seller is a friend and now is good R at expensive. I have the following questions: 1) What value does the car still have, i.e. with a working engine ? The car is built in 1995 and has 133000km down. It is a metallic blue coupe and has full equipment. In 1997 the (half-) automatic transmission (?) has been replaced for a 5-speed manual transmission. The car probably had problems often, making it a proper impression on me. 2) How can the damage best be repaired – replacement engine, engine reusable How do I get a cheap replacement engine? What tips do you have – what can you advise me? Greeting Harald