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Dear James, I have a 96 Toyota T-100 3.4L V6. My number six injector is not opening up and spraying fuel. So far I have put a new fuel pump in, a new fuel filter and fuel pressure regulator. I even put in new injector in it as well. I checked the injector connection and it has juice going to it, I also tried a friends computer from his 96 Toyota and it still did it work. I am out of ideas and don’t know anymore areas to look. I took to shop and they said the code is P0306 (misfire on cylinder six) Josh S, Lakeland Fl.

Josh, I suspect you are chasing the wrong cylinder that is misfiring. Toyota’s are notorious for setting codes on cylinders that not at fault. I have had several Toyotas come in over the years with a misfire code on a certain cylinder, only to find out another cylinder is the one that is misfiring. Here is what I am going to suggest: (to verify that you are working on the right cylinder that is misfiring) While the truck is idling remove one plug wire at a time to verify the cylinder is “firing” or not. Three plug wires are easy to get to. The other cylinders have coils attached and will require you to remove the coils while running to verify they are working as they should. This type ignition system can show a misfire on a cylinder and it MAY be the companion cylinder that is doing the misfire. Not the cylinder the computer flagged for misfiring. Now to your question about your injector not firing as it should. When you turn your key to the “on” position battery voltage is constantly supplied to the injectors at all times. What fires the injectors is the computer giving the injector a momentary “ground”. This is what allows the injector to work. A broken wire from the computer to the injector might be the cause of your problem. So a wiring schematic and a good digital multi meter will be needed. Best advice I can give to keep your sanity is to find the best shop in your town and pay them to fix it with a warranty. If it was easy to repair cars then everyone would want to do this for a profession. Only us diehard “gear heads” enjoy the challenge, and relish in the thought of fixing things that others can’t. Live long and prosper in 2012. James Morris


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