Wont idle right or run right! Please help.

[slidinhusky62 0]

I have just bought my 1st G60 Corrado and it will not run great. I have done my research on my problem and have tried a few things but it dont seem to help. First it wont idle good. It will almost die sometimes and other times it will rev higher. It only seems to die when I am driving at night with lights on and using power? (has new alternator and battery)Also when I go to kick the pedal down it is like the engine is cutting out. It does not have to be wide open either. I can ease into the pedal and it will go all the way to red line without a problem. Or when it start to cut out I will back off the pedal a bit and will be fine again.(has new fuel pump) And I noticed the the gas pedal is hard to push. Havent found any info on this one yet. Hope someone can get me in the right direction.