QuestionQUESTION: How do i fix a diagnosis code P0304 a misfire in 4 in a 1996 Taurus with 3.0L compression good 120 changed plugs wires egr backpressure sensor vacuum solenoid vehicle speed sensor coil pack injector what else?
ANSWER: i hope you didn't replace all those parts for a 304 code-first when you receive a code p0304 for example that is not a diagnosis-that is a clue to help in the diagnosis-although some of the things you have replaced could have caused the 304 others wouldn't and if they were replaced for this code you wasted your money-barring any computer fault the things that can cause this code and still have good compression are
in no particular order
plugs/wires/coil/leaking intake or vacuum leak/broke valve spring/sticking valve/dirty or bad injector/loose or dirty connection on coil/injector/pcm/and please don't put bosch platinum plugs in this car/cam sensor/synchronizer/low fuel pressure (rare to show on one cylinder but have seen it) and other things-
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QUESTION: ok so you have told me most of what i replaced, now to get to your knowledge now, what could cause this and what do i check for? and how do i check with out purchasing the new items you have told me that i have not already replaced? it says the same thing in my book that you have said, and that is why ive replaced the items cheapest to most expensive in that order. what would you suggest i look at next? ive checked for vacuum/pressure leaks? have not checked fuel pressure yet? have not done the oil in cylinder chamber yet?
ANSWER: i think you may be missing the point yes i named some things you have replaced and a lot you have not that can cause this problem-you replaced a couple of the most common things that cause this but what i am trying to say is there is a whole slew of things that could be but i can't and won't give you things to try, it does need to be diagnosed but that is something i can't tell you how to do step by step here. if you hear any squeaking type noise while running listen around rear of engine where transmission mounts and if it comes from this area replace synchronizer and cam sensor-unless plug is oil fouled forget about oil in chamber that won't be a problem other than that have it checked out by a reputable garage
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QUESTION: hi,
yes i am working on the first cylinder front of car passenger side closest to the alt, another question ive taken the injector plug wires and switched them number four 4 with number five 5 and i still get a reading of P0304, which means number four 4 cylinder, question i have is are the injector wires married to or assigned to a specific cylinder? or could i put ANY injector wire to ANY injector? if so in theory wouldnt number fours 4 wire become number five or would number four 4 even tho hooked to 5 injector think it was number 4 still? have i confused you yet??????? what im trying to say is if i move four to five does it (PCM) still think it is connected to four when in reality it is connected to five?? or does it sense it is connected to five and not four where it use to be connected.. and still give me the code P0304 or since i switched injector wires being hoofed up to five IF it was in the wiring it would read P0305?? and if in the cylinder it would still read P0304. hope this made sense???? if you or any body would like to call me let me know your email and i will send it to you so i can try to explain what i have written above??
thanks so much for your time
Robert
Answerspark plug wire 1 and 4, 2 and 5, 6 and 3 go together-as far as injector electrical wires they go to specific cylinders-but if you swapped 4 and 5 you should get two misfire codes because neither cylinder would be getting fuel when its turn came up-but you can swapped paired plug wires because both sides of the coil are fired at once so the cylinder with fuel in the cylinder would have the least resistance and spark would fire the fuel on that cylinder spark for the other cylinder is called waste spark. the computer picks up misfire from engine rpm per cylinder a misfiring cylinder will slow the rpm when that cylinders turn comes up and the rpm would speed back up on the next correctly firing cylinder and the pcm sees that because of ckp or cam sensors.-have your vehicle checked out.
