I just bought a 1991 300sl and love the car. Although I have one (maybe two) frustraring problems. When starting the car it will immediately stall. The second hit of the key the car will start and sputter for a few seconds and sometimes stall. There is a smell of gas in the garage. The previous owner took the car to a shop and they replaced the timing chain. That shop told me the next step would be to replace the two fuel pumps($500) I took the car to another shop and he thought it was the fuel injectors. He cleaned them and replaced the filters($400) The car runs the same. Now he wants to replace the injectors($500) Im not sure what to do. Any suggestions? Are the injectors easy to replace? Do they require any tricks or special tools? the car has 140000 miles. After starting and running for a minute the car runs perfect.