1994 Toyota Land Cruiser

I HAVE BEEN TRYING TO HAVE DEFECT REPAIRED IN MY TRUCK TO NO AVAIL. THE TRUCK HAS BEEN IN AND OUT OF SERVICE AT RIVERHEAD TOYOTA FOR MANY MONTHS AND IS NOW AT SMITHTOWN TOYOTA. THE ORIGINAL PROBLEM AND NOW CURRENT PROPLEM IS NOW POWER TO ACCELERATE FROM A STOPPED POSITION FOR EG. AT TRAFFIC LIGHT OR STOP SIGN. THIS PUTS BOTH MY FAMILY AND OTHERS DRIVING AROUND ME AT RISK. WHAT MAKES THE SITUATION EVEN MORE DANGEROUS IS THE PROBLEM IS INTERMITTENT, SO YOU NEVER KNOW WHEN IT MAY HAPPEN. THE PROBLEM WAS SUPPOSEDLY FIXED AND THE CAR WAS DRIVING FINE, BUT THEN THE CHECK ENGINE LIGHT CAME ON. I BROUGHT IT BACK AND THEY TOLD ME IT WAS THE OXYGEN SENSORS. I SAID, " I THOGHT THAT WAS A RECALL THAT WAS ALREADY REPLACED A WHILE AGO. THEY SAID THEY HAD TO BE REPLACED AND NEVER GAVE ME AN ANSWER WHETHER OR NOT THEY WERE ALREADY REPLACED BEFORE. I HAVE ASKED FOR ALL REPAIR RECORDS FOR MY CAR AND WAS TOLD THEY DON'T HAVE ANY IN MY FILE. I REALLY NEED YOUR HELP. THEY ARE NOW TELLING ME THAT MY CAR NEEDS A WIRING HARNESS. COULD THIS ALL BE RELATED TO THE FAULTY OXYGEN SENSORS?? I READ THAT THEY CAUSED THERMAL STRESS TO THE WIRING??? I HAVE TWO SMALL CHILDREN AND I AM 5 MONTHS PREGNANT AND REALLY NEED A SAFE CAR. PLEASE HELP!!! THANK YOU!!