My w126 280 se wont idle when its at Normal operating temp (80°c) i also noticed a lot of blue/white smoke coming out of the exhaust.
And in order to keep it going at stop lights i have to rev the engine to about 1500 rpm and sometimes it dies when taking a turn wich can get scary sometimes and when it dies i have to keep the throttle all the way in to start it .
I just replaced the powerplant witha a 2.8L from a w123 with about 300k km on it wich i dont think is old for such a engine since my old engine had a little over 400k km.
what could be wrong? fuel pump, filter, vacum lines, ........