88+ random miss fires
 

Hey guys,

So I have a 2012 MS3 with 17k miles, all stocks, no mods. I was merging on traffic last week and got on it 3rd gear and shift at around 5krpm. Engine light came on. Went to dealer this Monday and service guy said they had a similar case with random miss fires (100+), they ended replaced the flywheel for the other guy (no idea what flywheel has to do with it).

So they clear the code and asked me to come back if it happens again since he said i only have like 2 or 3 miss fires.

Today on the highway doing 70mph and the light came on again, went to the dealer and he said it has like 88 random miss fires. THey gave me a loaner and they said they gonna replace the plugs.

Anyone have this type of experience?

this is new on me man, I have yet to have any speeds come in the dealership for this issue.
But I got one question. When the cel came on was it a steady light or a blinking light. Steady light is ok, blinking light means shit is broke and damage can possibly be done to the engine if you let that light keep blinking.
keep us updated I am going to see if any tsb's are out for this.

Funny that you asked. The first time when it came on, it was steady first, then it started to flash and never seen it again. BUT today, it's different story, it was flashing every 5 seconds for about 5 to 6 times. I know it wasn't a good sign when I saw it flashes that many times, so I made the call and ask to come in right the way.... they gonna have my car until next week.

I really don't think changing the spark plugs would solve it, I don't have knowledge to back it up but the only thing I can explain is when the engine light started to flash, the car rides fine, no strange noise or lost of power, even when parked there wasn't any hesitation; that's why I don't think it'd be the spark plugs.

do you know what the code was? random misfire or cylinder specific?

could be an injector or coil going out brussel sprout.

I believe it was p0300, any thoughts?

Sounds to me like bring it to the dealer and let them hash it out. Misfire could be like 20 things and more on a boosted car.

Edit: flashing engine light means the car shut down a cylinder to prevent cat damage. Flashing engine light is bad news.
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man, that's random misfire, i believe. which is the hard one to figure out..

looks like the dealer's gonna have to sort this one for you. i don't even know where to begin..
although you could go VIP, then download the shop manual for the car. there are diagnostic flowcharts in there, could be useful.

you do not want to see the diag flow chart for this, it is a nightmare. hate to say this but shits broke.

And tddvrn love the little gif thing you got going on that shit is funny

Um, somethings not right here and I'm also not sure what the flywheel has to do with misfires...pretty much nothing.

Ask for the codes and the definitions. The CPU will tell you where the misfires are happening. It's actually very specific.
IDK @ 17K you wouldn't need plugs until at least 30k-45k. Ask them to do an induction service and check the fuel pump at 30k. not now. (which covers cleaning the fuel injectors) Seriously, start off here. For the speed 3's theres not many problems but at the fuel pump, suspension, and clutch, and turbo. I'll look monday for TSB's for the speed3. the only open recall I know of is for the VVT.

Be persistent and easy going they'll be eating out of your hand.

BTW. Check you gas cap dude.

i all ready looked there are no tsb for misfires or anything along that line.

Didn't think so, but I wanted to make sure. If you've already checked...thank you.

ya np I looked just the diag tree for random miss fire is a bitch

ahh, that's just great. So that's pretty much what they're gonna do. Change the plugs, clear the code. Few days later, light comes back on; bring car back to the dealer, and try something else, process elimination ahhhh, i see a long road ahead.

There is a reason that your car has just suddenly done this. Spark plugs and coil packs do not just go bad unless you own a RX8 and that is a different beast in its self. When the cel came on was the car bucking, sputtering acting like it had loss of power

Maybe your V- Tech solenoid is going out

Not at all, both times. There wasn't any lost of power, hesitation, bucking and sputtering... nothing that I can feel or tell, I even parked my car and let it run and opened up the hood to hear, but it ran pretty normal...

Does our crank position sensor read the flywheel? If so that's why flywheel matters. Crank position sensor is what checks for misfires by watching crank rotation speed and steadiness.

If not, it could also be a flywheel balance issue cause a misfire, more than likely its something else. I would just go to the dealer.
Tell em I don't want it back til it's fixed.

At fiat we have a guy lemon law a car over something stupider

Also gas cap throes a p0440-444. Not a misfire
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The tone ring for the CKP is on the crank pulley.


Tapadatass

we have a dual mass flywheel. if parts are damaged inside of it then yes it can cause a false misfire reading

just one example
Trouble shooting misfire codes - Rennlist Discussion Forums

I know what the gas codes are dude. Just being funny about the guys situation. Just never heard of a flywheel causing a false reading. That will be Interesting to me.

Let us know what it is. I'm curious.

Well guys, a little update from the "service advisor", he called today and said they changed out the plugs and still have couple of miss fires (I knew it)! So they sent out fuel sample and awaiting for the result. arrggg, did I got a lemon? :sad:

a "fuel sample?" sounds like he's buying time and has no idea. It is a tough problem to sort out but keep in mind it could be a very simple and harmless fix so don't lose faith yet. Once they get enough eyes on the car (or throw enough parts at it) it'll run good again.

have you tried a different gas station?

Yea, if they keep on replacing parts, I might end up with a whole new car :) @Harvey, I've been using the same two gas station since I bought the car, I doubt it'd be the gas... I guess we'll see the result is tomorrow.. can't wait what they gonna tell me. If they can't still figure it out, should I take the car back? He said the engine light didn't come up anymore but some how they can still see it has miss fires, couple of them.

They're testing the volatility of your fuel to make sure you don't have summer blend low volatility fuel in your vehicle, which could cause poor atomization and subsequent misfires in colder weather

no, dont take it back if it's not fixed

They're ruling out spark and fuel problems. Sounds like routine misfire diag to me.

Mine had random misfires and my check engine light was flashing the one afternoon. I had an aftermarket intake and the breather hose was loose on the intake side. They didn't even check my plugs. That happened at about 17K miles. I assume they would check all the intake connections. I tightened up that hose and haven't had any problem since them. They didn't tell me how many misfires i had but the car drove fine when the light was flashing.

Isn't it better, for example, if they try to fix the car but it just does not work to try a different dealer. Sometimes you never know who works at those places.

My car is currently in the dealership for this same reason. Purchased a little over two weeks ago, the first friday the light came on and I changed the plugs. Light went off after a few miles on new plugs and didnt come back on until last friday. It had basically the same thing, light on and absolutely no loss in performance or drivability. I took it in on monday and they have yet to actually find out what is causing the misfires. Anything I can suggest to them to maybe give them ideas they haven't tried?

BTW car is 06 MS6 with 81k

Ok guys, I finally got my car back, I kinda like driving automatic... I've been driving manual for 14 years and it's weird feeling to drive auto cuz I feel like I don't have to do anything but just drive.
Anyway, so I'm gonna write up what they have done, apparently this is the 2nd case for them. Just a reminder, the other case, the guy had like 100+ miss fires in one cylinder, and he had a 12' Speed as well.

1. When the light first came on, they clear the code and asked me to come back if it happens because it had only two miss fires.
2. The engine came back on after a week, but this time the car had like 88 miss fires in cylinder 3 and couples in cylinder 4. Changed all the plugs and still had like couple of miss fires here and there.
3. Then, they changed the steering sensor? Still have miss fires
4. So, they swapped the coils around from cylinder to cylinder, from 2 to 1, 3 to 2, 4 to 3, 1 to 4, and still didn't work.
5. Finally changed the flywheel and apparently that solved the problem.

I was the second case the dealer had to change the flywheel.

It's the damn dual mass flywheel. Those guys are pretty good to catch that

Thanks for posting. This will likely come up again and a dealer might have trouble finding the solution. In that case a little research here will point them in the right direction.

When I thought that my 2005 STi had a broken piston ringland the dealer did not know it was common problem. After talking to the service writer for a long time I left and came back and caught him on the NASIOC forums lol.

thanks for the update, I will keep this in mind for sure if a car happens to comes in for a massive amount of misfires.

good on ya for sharing this

i always think coils when i hear missfire since i had a 1.8t GTI for a while...

Happened to me. They replaced my coil pack, pcv valve, spark plugs, injectors, and they took my intake manifold off and cleaned it as much as they could. No problems since!