Kia Hampster Car from 2011 With Misfire

So, the wife’s car is acting up and I’m not sure what I should check or if the specific symptoms should lead me to any potential suspects…

She has a 2011 Kia Soul. About two weeks ago the battery went flat. It was 6 months old so I took it in to have it charged and tested. When it was tested prior to charging I was informed that it was good, but dead. When I returned to retrieve it I was told the battery still tested good, but was not taking a charge. Mind you this was at Autozone, so my confidence in the staff’s diagnostic abilities is not high…

In any event, the battery was exchanged uneed waranty, after which the vehicle appeared fine. I live in the midwest, and this past weekend we had a considerable amount of snow. The beginning of the misfire began right after the first time my wife got the car out in the snow and got it stuck. According to the testing device, the misfire is on cylinder 1 and cylinder 1 only. It also seems to smooth out over about 2k rpms, but that may just be washing out the feeling. Even more interesting to me after investigating the issue is that the misfire does not seem to begin until after the car has warmed up. The first 5 to 10 miles of driving are trouble free, but after it has warmed up the issue begins to develop. The CEL is on steady, but occasionally blinks once or twice when taking off from a light. Not every time I take off, not every light, but every once in awhile.

Sorry for the information overload, but I like to be thorough when asking for advice. Oh, it is the 1.6 engine running synthetic, base model if that helps or makes a difference.

Have a compression test done on the cylinder when the engine is hot and misfiring. That cylinder might have low compression due to a valve out of adjustment. If so, have the valve lash adjusted and see if that eliminates the misfire. I believe that engine has valves that require mechanical adjustment.

Out of adjustment valves caused numerous misfire problems with first generation CRV engines (I have one of them), so it can and does happen.

If compression is good, then another possibility is lack of spark. When the misfire is present, have a mechanic check for spark. Possible culprits: bad spark plug, bad plug wire, etc.

“The battery still tested good, but was not taking a charge” --not taking a charge is pretty much the textbook definition of a bad battery. What did the fine folks at Autozone think it tested good for, a boat anchor? Or did they mean that your alternator was not charging the battery?

I don’t think the battery problem is related, unless you had the car jump started, which can sometimes damage the ECM or other electronic circuits.

When the ECM reports a misfire that means it measured the crankshaft rotation & it slowed down instead of speeding up on that particular firing on that particular spark plug. If a spark plug fires, it should create an explosion and cause the crankshaft to immediately speed up. So it pretty much has to mean one of three things

  1. The spark plug didn’t fire
  2. The fuel/air mixture wasn’t correct
  3. The fuel/air mixture isn’t being appropriately compressed

What you do first depends on a guessing game. Think it is number 3? Do a compression test and valve test. Think it is number 2, fuel pressure test, maybe an injector test. Number 1, check for a consistent visible spark.

This is the kind of problem where having the manufacturer’s scan tool is very helpful. If you take it to a mechanic, make sure they have the correct Kia scan tool for this car. Does Kia give you access to the factory service information on their website? Some Korean manufacturers do that for the owners, for free. If so, you could see what it says in the factor service manual to do when that particular code appears.

BTW, it is important to get this addressed w/due speed. Misfires can damage the very expensive catalytic converter.

@oblivion I couldn’t say honestly. They have a lovely little box they hook up to the battery that tells them if it is good or bad. I’m skeptical, and as far as I’m concerned it didn’t take a charge so that’s that. It’s a bad battery… so far as being used in a car is concerned.

@jesmed I thought that the 1.6 did not have adjustable valves? I was aware of it with the 2.0… anyway, I might tackle that job myself. I’ve done valve adjustments on BMWs and motorcycles before, so I think I’m reasonably up to the challenge. Do you think there is a write up somewhere?

@GeorgeSanJose I’m getting it taken care of this weekend. It’s annoying if nothing else, and I’m aware of the danger to the cat from gasoline passing though without being burned. We have a second car and a flexible enough schedule to make due with the one vehicle for a bit if needed. Wish the Kia was as tough as my Outback though.

I could be wrong, maybe it’s only to 2.0 liter that has adjustable valves.

According to what I see here, for the 2011 Kia Soul 1.6L, it does require a valve clearance check and adjustment as part of routine maintenance.

Valve clearance at 20°C

Intake 0.17 - 0.23mm
Exhaust 0.22 - 0.28mm

This might be covered by the factory warranty. It would be worth checking.

@VOLVO V70 if it isn’t a simple fix that’s exactly where I’ll be going. I believe that the car is still under warranty so that’s where I’ll be headed if things don’t work out for me. I just like to know as much as I can before taking it in.

@GeorgeSanJose that’s my project tomorrow. I just hope I can get valve shims from the mouth breathers at O’Reilly’s. I don’t know what they’re like in your neighborhood, but in mine they don’t know the difference between a crowfoot and a 1/2" impact.

Well you can do the valve adjustment, it should fix it best of luck. But if it does not fix it and you take it in (to the dealer) under warranty, keep your mouth shut. Even a single mistake they will tell you that you voided your warranty. So talk smart. Note: I would make them do the valve adjustment.

If the CEL is on steady and occasionally blinks, you need to get the codes read pronto, and as Umair said, you need to work with the dealer for everything or risk voiding your warranty.

But I urge you, do not delay getting this checked out. If you’d like, post the codes here and we’ll try to help you understand them, but let the dealer do the diagnosis and fix the car.

Thought I’d report back. Kind of odd. I moved the plugs around, but the misfire decided to stay put on cylinder 1. Recognizing that it was overdue I went ahead and replaced the plugs. The CEL has not returned since… so… that’s that for now.

Thank you for the report back. I don’t think you’ve seen the end of this one yet though. For your sake, though, I hope I’m wrong about that.

Did you check the valve clearances too? Did they require any adjustments? I think a mis-adjusted valve could potentially cause a spark plug to overheat and eventually damage it, that’s why I’m asking. Other than that, beyond just a sample defect, it’s hard to explain why a 2011 would have a spark plug fail. I can see the gap opening, maybe causing some pinging, but not enough to cause a complete misfire. Anyway, glad you got it fixed. Hope it was in fact just a faulty spark plug and the new plugs keep it fixed. Best of luck.