Engine Performance problem
1987 Volvo 740 4 cyl Two Wheel Drive Automatic 186455 miles
hello, I was driving on the hwy at about 70mph yesterday when my engine started to sputter badly. At first when I let off the gas a little bit the engine would straighten up and heve normal power but then began to stumbleand black smoke began pouring from the exhaust. After maybe 3 min of this the engine died and would crank but not start. I waited 2-3 mins and the engine starts and idles fine then dies again after 2 min. I have recently replaced almost the entire ignition system and replaced the tank fuel pump and fuel filter.