1985 380sl a bit sluggish

[KERRYMARCY]

Hi, I have a 1985 380sl. It is in awesome shape with only 68,000 miles. I recently bought this car which was in storage for the last 4 years. The engine runs great but when the accelerator is pressed, it seems to lack power and takes a while to respond. It takes longer than normal to get into passing gear and sometimes it will not go into passing gear at all. I am going to replace the plugs, wires, cap and rotor this weekend. I've put Techron fuel system cleaner in my last two fill-ups thinking that the injectors and fuel system may be dirty or partially clogged. Is there possibly something else I should be looking for? I would appreciate any feedback on this issue.

Thanks, Kerry