My 87 pickup cranks but it won't start. I have spark from the coil. I replaced the cap and rotor(old rotor was cracked). I also replaced the wires and plugs because it felt like the old wires were barely contacting on to the plugs. Still wouldn't crank after this. From cranking and trying to find spark it throws gas out of the exhaust. Any ideas?? Hate to send it to Nissan heaven. thanks