Question about 2004 Kia Optima

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My 04 Kia Optima will start but then it runs rough. It acts like I might have trash or water in my fuel line. Does anyone know where the fuel line filter is located, also could this be a problem with fuel injector. I doesn't run like this all of the time. It will be rough for a week or so, and then it will run fine for a week or so and then the process is repeated. I have had it hooked up to the computer and it shows no problems. Any suggestions please?

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Put a can of a product called "Seafoam" in the gas tank. Also do the following procedure.

Here are some of the causes of surges, stalls at stops, slow idle speed, erratic idle speed, rough idle and engine hesitation (and other problems), it is in most cases the idle speed control air-bypass valve and or throttle valve and upper intake, these area's get full of gunk and combustion residue over the miles and cause idle issues (stalls, low idle) like yours, Get a can of intake cleaner from any local parts store, not carb spray, intake cleaner, it is made by a company called CRC, remove the air intake hose to the engine, hold the idle high so the engine won't stall, then spray the can of cleaner into the intake while keeping the engine running, use at least 1/2 the can, shut down the engine and disconnect the battery for 5 minutes, then restart and complete a number of mixed driving cycles, town, freeway, stop and go etc., after a few days the problem will go away as the system will relearn to the clean intake.

Posted on Jun 19, 2017


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Posted on Jan 02, 2017


SOURCE: 2004 kia optima problem

possibly mass air flow meter, if faulty dosent bring light on.

Posted on Oct 16, 2008

  • 87 Answers

SOURCE: Location of a 2002 kia optima fuel filter

Hi on this car the fuel filter is in the fuel pump so the pump as a whole will be replaced. To get to it you will have to remove the rear seat bottom cushion. There are 2 12m bolts inbetween the top cushion and the bottom. remove them and then on the front of the bottom cushion there will be 2 plastic clips pull up on them and the cushion will pop up and you will see the acc panel for the pump.

Posted on Mar 27, 2009

  • 31 Answers

SOURCE: WOndering average repair cost on a 04 kia optima

If the flywheel is damaged your looking at $2,500.00

Posted on Sep 16, 2009

  • 347 Answers

SOURCE: where can i see the wiring diagram for a 04 kia optima for free?

try replacing the starter

Posted on Oct 30, 2009

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Check the following website. you have to sign up but this is direct from kia.

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