280e running help
 

Hello,
I am looking for input on my 77 280e, when started it runs rough, when you press on the gas it falls on its face and will sputter and backfire then slowly increase in revs. It seems way off on power. some white smoke out the tailpipe and smells gassy. about the same at running temp also.
I have set the timing at 10 degrees BTDC new plugs, wire fuel pump and filter. The car has set idle for about ten years and the engine has an unknown history. (old gas was drained and new put in)
Has good oil pressure and good compression.
Any input would be appreciated.
thanks