DIY Repair for Engine Misfires

10

Asked by alanrrios Aug 07, 2019 at 04:13 PM about the Kia Rio

Question type: Maintenance & Repair

Hello,

I have a 2006 Kia Rio that is currently experiencing some engine issues. A diagnostic at Auto Zone confirmed the issue is with 2 out of the 4 cylinders misfiring. I've done a bit of research and so far this seems like something I may be able to resolve myself. However, I would like some assistance in diagnosing the issue to make sure I am not in over my head.

I first noticed the issue because my car was slow to accelerate. It felt as if the engine was significantly weaker. I checked my engine oil, because I wasn't sure where else to start, and noticed it was really low even though I was not due for an oil change. I went to nearby shop and they took note that there oil leaking over the top of the engine and most likely the culprit of the leak. I've since added oil to the engine but it is still bad. After receiving some advice from a bystander they recommended I go to Auto Zone for a diagnostic. Auto Zone confirmed my engine had a couple of misfiring cylinders.
The bystander's advice was that it could be a fuel injector problem due to the engine spitting oil.
The representative at Auto Zone mentioned that it could be an issue with spark plugs. When I mentioned the ignition coils they let me know that it could be an issue with the ignition coils being covered with oil.

I haven't done TOO much research but I've considered a few solutions. Those are as follows, in order that I would want to try:

1.) Clean the ignition coils so that there is no oil present.
2.) Replace the ignition coils where engine misfire is present.
3.) Get an expensive diagnostic from a mechanic to ensure there is no other issues such as a fuel injector problem and then follow it up with an expensive repair.

My goal with this post is to get more advice on the issue so that I can make a better decision on how to continue. My biggest gripe with this now is how this issue could have started. If I were to replace the ignition coils without addressing the issue that caused the ignition coils to have issues in the first place, such as what caused them to get covered in oil, then I would have spent money on a repair that didn't address the underlying issue.

Best case scenario is that cleaning the engine coils and making sure they are free of oil fixes the problem. Worst case scenario is that I need to get a diagnostic done to find that there is a deeper, more expensive problem.

Thank y'all for your assistance.

2 Answers

41,330

Remove the ignition coils and replace the spark plugs at a minimum. Inspect Ignition coil #2 and #4 for oil. You might want to consider replacing the valve cover gasket if the oil is really bad. You can swap the coils from one cylinder to another and see if the CEL stays on and if the misfire codes move from cylinder to cylinder. Then you know it is the coils.

2 people found this helpful.
10

I took your advice and switch engine coils 1 and 2 at home before heading to Auto Zone for an updated diagnostic. The car was still rough while idle and felt different while riding. At Auto Zone the updated diagnostic showed that only cylinder 4 was misfiring now. I switched 3 and 4 there and got an updated diagnostic. At first it was all clear but when I accelerated to leave the parking the rough ride started again. The last diagnostic showed that cylinder 3 was now misfiring. All engine coils were still covered in oil. I was not able to figure out an answer of where that oil would be coming from and if it would require a more intensive fix. So to recap: Swapping engine coils 1 and 2 fixed the cylinder 2 misfiring issue on 2. Swapping engine coils 3 and 4 confirmed issue with single engine coil now on cylinder 3. I will be continuing by buying a new engine coil online and swapping it out.

1 people found this helpful.

Your Answer:

CarGurus Experts

  • #1
    brotherben
    Reputation
    2,300
  • #2
    flippinthemadstyles
    Reputation
    1,080
  • #3
    T_S_T
    Reputation
    810
View All

Find great deals from top-rated dealers

Search

Related Models For Sale

Used Kia Forte
75 Great Deals out of 1,343 listings starting at $2,499
Used Toyota Corolla
151 Great Deals out of 2,438 listings starting at $4,295
Used Honda Civic
195 Great Deals out of 4,054 listings starting at $440
Used Kia Rio5
31 Great Deals out of 499 listings starting at $3,699
Used Hyundai Accent
26 Great Deals out of 464 listings starting at $2,499
Used Hyundai Elantra
156 Great Deals out of 4,214 listings starting at $100
Used Kia Soul
38 Great Deals out of 995 listings starting at $2,000
Used Kia Optima
12 Great Deals out of 270 listings starting at $3,920
Used Toyota Camry
60 Great Deals out of 1,072 listings starting at $3,995
Used Kia Sportage
42 Great Deals out of 1,927 listings starting at $1,054
Used Kia K4
909 listings starting at $23,995
Used Honda Accord
55 Great Deals out of 995 listings starting at $2,000
Used Kia K5
5 Great Deals out of 61 listings starting at $20,495
Used Nissan Sentra
65 Great Deals out of 1,744 listings starting at $1,995
Used Ford Focus
19 Great Deals out of 520 listings starting at $2,499

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use. Content will be removed if CarGurus becomes aware that it violates our policies.