p0316 and p0304 NEED HELP PLEASE

roodyl · #1 (**permalink**) 07-02-2009, 12:57 AM

hi,
everyone i had posted a thread here about a month ago and everyone here was so helpful and i would like to thank you all for that. but now i am back again. my 2003 ford ranger 3.0 v6 is having a misfire on start up and it is located in the forth cylinder and i was wondering if anyone here had any suggestions on where to start to get rid of this problem. i have already changed all my plugs wires and even the coil pack cleaned out the maf and looked for possible leaks. the car shakes really bad at lights and the check engine light starts to flash. does anyone have i diagram of where all the cylinder numbers are at and maybe the firing order? thank you all so much

sincerely

rudy

Rockledge · #2 (**permalink**) 07-02-2009, 10:05 AM

Here's a diagram:

P0316 is a Misfire Detection Monitor code

P0304 means Cylinder #4 is misfiring. You should check for fuel and spark at that cylinder.

roodyl · #3 (**permalink**) 07-02-2009, 10:49 AM

thank you
would you happen to have to numbers for the coil pack to ?

Rockledge · #4 (**permalink**) 07-02-2009, 11:13 AM

Yes, as matter of fact:

roodyl · #5 (**permalink**) 07-02-2009, 09:33 PM

thanks,
so when i wired my car up according to the diagrams the car would not fire up. Do you have any ideas why it might be doing that? thanks for the coil pack diagram though it was really helpful the after market one did not have any lables on it

Rockledge · #6 (**permalink**) 07-02-2009, 11:23 PM

Here's another diagram showing the coil pack on a 2003 3.0L. Double check the plug wires.

roodyl · #7 (**permalink**) 07-03-2009, 08:25 PM

ok so that one worked perfect i double check the wiring to match the diagram and everything was correct put it back on the obd and still had a misfire and the misfire on start up any suggestions on where else to start to correct the probelm thank you

g_k50 · #8 (**permalink**) 07-03-2009, 08:42 PM

Were any of these codes present? p0136, po156, po171, po172, p0175, p1130, p1150?

Check your wires? might be too much resistance?

roodyl · #9 (**permalink**) 07-03-2009, 08:55 PM

no none of those were present just p0316 and p0304 i scanned it several times

Bear River · #10 (**permalink**) 07-04-2009, 01:10 AM

The misfire may not be the result of weak spark, but could be a sign of a bad injector. If you had a bad coil, wire, or plug, would should have had a P0301 and a P0304, since those are linked and will miss together when a coil goes out.

david53ford · #11 (**permalink**) 07-04-2009, 01:23 AM

you may have a compression problem

roodyl · #12 (**permalink**) 07-04-2009, 01:57 PM

what would be the best way to test if hte injectors are working properly?

g_k50 · #13 (**permalink**) 07-05-2009, 12:34 AM

I tested mine with a fuel pressure gauge.

Key On Engine Off, pressure should be present with the pump running for a short time then turning off. There should be no slow leak down of the pressure.

Engine running the pressure should be constant, pressure should go up slightly when the vacuum is removed from the fuel pressure regulator that confirms your fuel pressure regulator is working.

Engine off there should be very little leak down of pressure. Alot of pressure leakdown indicates injectors are stuck open and are leaking fuel into the intake runner. Use a good injector cleaner in the gas tank to slowly clean the injectors, or have a mechanic clean them quickly with a tool.

roodyl · #14 (**permalink**) 07-05-2009, 01:49 PM

hi everyone

hope you all had a great forth of july. so i found out the probelm with my car its a bad fuel injector does anyone here have a diagram and fuel injecotr numbers so i can swamp them out with my new ones and do i have to do all of them or jsut one would be fine