I jump started my 92 MBZ R129, 500. I connected the terminals WRONG (pos to neg). The battery on the car that was on started to smoke. I discconected the cables. I jump started my R129 the propper way, and my instrument cluster was not working. I replaced the fuse and everything works except the MPG guage.

Now the car is hard to start, idles very rough, sometimes turns off. I can drive it, but it feels like its driving on 4 cylinders NO POWER. Missfiers bad.

Please...