98 malibu turn signals flash wierd when headlights on

hey to anyone that might know, we have a 98 malibu the intake manifold gasket blew, replaced it then got dreaded p0300 code found out that it had to bad injectors replaced those now everything works fine except when the headlights are on the turn signals flash real fast and they both blink. ( left one on they both blink right one on they both blink). my hazards work like normal wether headlights are on or off just the turn signals? can someone please help i dont have time to look at all 103 pages to find any other threads about this issue please help? by the way these cars suck worst than any other car i've ever seen