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OBD Code P0304

OK, last night on the way home from work I noticed surging/stumbling/something generally not right between 1500-2000 rpm. I Went to WOT a time or two, both times the check engine light would flash a time or two right after then go out. I eased it home, right before I got there the light came on and stayed on. Took it by autozone a minute ago, their scanner showed code P0304; of course, all the guy could tell me was that cylinder 4 was misfiring, that it could be plugs, coil pack, wires, etc....nothing that I couldn't guess for myself.

Google search only turned up the following info:

A code P0304 may mean that one or more of the following has happened:

Faulty spark plug or wire Faulty coil (pack) Faulty oxygen sensor(s) Faulty fuel injector Burned exhaust valve Faulty catalytic converter(s) Running out of fuel Poor compression Defective computer

I've got 53k miles...I'm guessing it's time for plugs, although the dealer says 60k. Guesses, anyone, before I either start throwing on parts or bend over and go to the dealer?

Wabbitslayer

01 GT vert

Service Engine Soon Light---Operational

Reply to
wabbitslayer
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Well? If he could just lean over and yank off the offending part, he wouldnt be working there would he?

Gonna separate out the possibilities, Ignition, direct effect:

- that would be a weak injector driver, I would check ign wiring first

- obviously, see below

- easily found with cyl leak-down test

From the "Stray quark ripped through my PCM and damaged a bit on the #4 injector driver department":

discard, unless you consider "looks as if"

First do a search on the alt.autos.ford and this group looking for similar, IIRC likely to be a boot... or maybe a coil pack

Second: the old trick of analysing plugs is still valid, pull # 4 and a couple others from both banks and compare them (LABEL THEM!)

- If you have a bad injector, O2 sensing will cause other plugs in bank to show over compensation

Gee, I cut the O2 sensor and forgot to paste it... well, if it's faulty then all the plugs on that side will show too lean or too rich

Reply to
Backyard Mechanic

well, looks like saturday morning I'll change plugs...about time for it anyway, if it's not the plug, they all needed changing anyway.

Although you should have seen me looking for the spark plugs on the sides of the heads... I even thought for a second, since I can't even see them from up top, the best way is probably to remove the wheel on each side and go in with a long extension....and then....DOH!

(I know...I know...what a dumbass)

Wabbitslayer

01 GT vert

Reply to
wabbitslayer

Hey... about every other day, i cant find my keys.. and I KNOW what they look like.

Reply to
Backyard Mechanic

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