help!!!

[burrrockym]

Ok. I have a 99 Kia and it is spitting and sputtering. It has always lacked a little for power but now can't even get it to go down the road. Starts fine. Keep getting codes p0301-p0304 and p604. Have changed all the sensors. unhooked the cat to see if it was plugged. Changed coil packs, plugs, wires wire harness. Don't know what else to do. Nothing seems to make a difference. Changed the fuel pump once a short while ago but still wondering if it is this? Please give me ideas. Like most others -ready to junk this piece of crap. By the way has 64000mi. Also to let you know it idles fine at times and sometimes even went down the road fine then would just lose all power and then it would be ok and not and so on. you get the picture. thanks in advance for your hellp

[LMP]

301-304 are misfires, plug 1 and 4, should not be there since you changed everything...
you say it starts easily..but anyway, what voltage do you have when it charges..should be 14.2 14.6 volts with engine running. Low voltage causes misfires and random operation...but of course, after a while, it would not start....

but 604 is rather rare....Internal control module RAM error.....can't say more than what is here:
www.avigex.ca/kia/P0604.pdf
....and at 64,000 miles, I would be very inclined to prepare for a new timing belt, if not already done. It can have slipped a cog or two already...an inspection of the timing marks should make or bust this as a cause of present problems...

[burrrockym]

Ok. Would the timing belt needing repair allow it to run perfect at an idle and act like its running out of fuel while accelerating? Alternator good. Gotta check on the timing but it just seems like it runs out of fuel. When you accelerate if I spray carb cleaner in the air flow it will run great again. I had put a used pump in there so just thinking maybe it's something to do with that. Idles great just as long as ya don't step on the gas! Let me know what ya think. The codes don't come back until you step on the accelerator for a few minutes. This thing is driving me nuts!!! I'll wait to hear back.

[LMP]

Originally Posted by burrrockym

.. Would the timing belt needing repair allow it to run perfect at an idle and act like its running out of fuel while accelerating.

it would seem t-belt it not the cause of this very behaviour....but there have been so many T-belt cases between 65 and 70k miles and above that preventive maintenance of that item is rather part of the game. Complete kits are available on e-bay between $60 and $150 depending on the contents.
I would certainly check for fuel rail pressure....should be 35-42 psi.
www.avigex.ca/kia/fuelpressuretest.pdf

[burrrockym]

Thanks a lot for all the info. Checked the timing belt it was replaced very recently as everything looks new. That's a good thing. We haven't had this vehicle very long. Seemed half way decent when it ran okay but that was about 3000 miles ago. That's all we've put on it. Anyhow will check out the fuel rail. We had replaced that and the injectors but who knows. It has to be something stupid, just can't figure out what. Seems like we've changed EVERYTHING!! Very frustrated at this point. We've spent more time working on it than driving it. Let ya know what we find out. If you think of any more

[LMP]

It is a fact that fuel supply (if that is in fact your problem), in a variety of ways, is like a plague with this vehicle....and except for the cases where the f.p. relay was the culprit and it solved the problem, the other cases all ended up whithout a clear cause identified and reported for all to remember.
So..when you find out, let your pain profit the others...
MAF is a possible suspect, but it should throw an error code...
Anyway, take nothing for granted: nothing is sure unless it is verified .

[burrrockym]

Did change the maf. Have checked the timing because figured you were right.... might as well.... also thought maybe it was causing the problem but it has been changed. Everything is new. So now I really don't know........ Think after I get it put back together I'm gonna take the first cat off and see if that is the cause. Either way when I figure it out (if I ever figure it out) really starting to wonder.. I will post. Thanks for all your help and if you think of any other possibilities I would appreciate all the help I can get!

[burrrockym]

Just an update..... took the first cataylic conv off and emptied the contents! Put it back on and was running great except for a misfire on 3. Changed the injector again on that one and so far so good. Hard to say how long that will last. I appreciate alll the help.