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THIS THING IS A NO START COLD. IT CRANKS LIKE CRAZY. HAS GOOD SPARK AND 60 POUNDS OF FUEL PRESSURE BUT THE INJECTORS DO NOT FIRE. WILL RUN IF ALTERNATIVE FUEL IF SPRAYED IN INTAKE. OUT OF NO WHERE IT WILL START AND WILL START REST OF DAY UNTILL IT SITS ALL NIGHT. RUNS FINE AFTER STARTED. NO CODES IN PCM. BACK PROBED ONE OF THE INJECTOR CONTROL WIRES WHILE NO START IS OCCURING. IT SHOWS INJECTOR GETS PULLED TO GROUND BUT GOES RIGHT BACK TO 12V. THERE IS NO INJECTOR SPIKE. SHOULDNT THERE BE A SPIKE EVEN CRANKING. NODE LGHT FLASHES AND THATS WHAT THE WAVEFORM LOOKS LIKE. I NEVER GET A SPIKE IN THE INJECTOR TILL IT STARTS. WHAT CAN CUASE THAT?
Thank you for the reply. I found someone had been in the maf harness and had tried to wire nut the wires back together after they had fell on the manifold. After repairing the harness my injector waveform looks normal again!
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