P0303 Misfire Cylinder 3 - Car running on 3 cylinders...Carbon Buildup??

[Ebbsnflows]

The facts:

2010 Audi A4 2.0L with 21,000 miles. Bone stock, no mods of any kind.

Car has ran flawlessly, without so much as a hiccup for 21,000 miles. Then this morning while my girlfriend is driving to work (at 60 mph on hwy), the car begins to studder/jerk violently and the CEL light begins to flash. No warning...just wham! Down to 3 cylinders. She pulls into a gas station and calls me. I show up, start the car and just as stated, it shakes/shudders (more than my 2010 Camaro SS with a nasty cam in it). I pull the engine code and it is a single code: P0303 Misfire on Cylinder 3.

Believing that the car was still under warranty, we had it towed to the stealership. We get a call an hour later..."Sorry...the warranty ran out 38 days ago". Nevermind that the car only has 21,000 miles on it. Begrudgingly I had them run a diagnostic ($130). 2 hours later I'm told that during troubleshooting, they swapped both the #3 coil pack and the #3 injector to another cylinder....but the problem remained on Cylinder #3. The service manager indicates that they believe it is a carbon buildup issue (and proceeds to give me the canned reasons: Bad fuel, poor driving habits, and not driving it enough). The cost is going to be $900.

My question to the experts here: If the problem was REALLY carbon buildup, Shouldn't we have experienced warning signs prior to today? (Rough idle, poor fuel economy, sluggish performance, occasional CELs)?? We experienced NONE of these issues. The car drove/performed perfectly...until this morning at 8:47 am, 12 miles from home (on a 67 degree morning). My understanding was that this was a gradual issue...not a "WHAM!" issue....and again with only 21K miles.

Also...wouldn't the misfire occur on multiple cylinders? Not just a single cylinder? I mean the same "crappy fuel" is being injected in cylinders 1,2 and 4 as well.

Opinions/Thoughts? Alternative causes?

[Fburg A4]

$900 is a lot to spend if there is a deeper problem and carbon cleaning doesnt fix it. Doesnt sound like a carbon issue for the reasons you said. They do any other diagnosis besides swap a coil pack and injector?

[Slick_B8]

Mines an 09 and its in because cylinder 4 has 0 compression. Mines cpo and still under warranty though so hopefully its covered. It did the same thing as yours and shuddered worse than modified v8 cammed to the max.

[Ebbsnflows]

Mines an 09 and its in because cylinder 4 has 0 compression. Mines cpo and still under warranty though so hopefully its covered. It did the same thing as yours and shuddered worse than modified v8 cammed to the max.

Well I REALLY hope that it isn't the case for ours. Although with the symptoms and the suddenness of the problem, I've actually been leaning toward something like this. To my knowledge they did not perform a compression check on the motor. When I speak to the service manager tomorrow, I will request they do this prior to cracking it open.

Do you know why/how you lost #4? Are you modified? Did it just lose fuel and run lean?

[Slick_B8]

I honestly dont know. It couldve been a plug or something but no way of knowing. I dont want to shell out 5k for a new engine either and if i do, im gonna go built on a budget. Not gonna go stock for that kind of money lol

[Tm030512]

Got the same code but that's because my injector in #3 is stuck open =/ Will work on this Friday along with a carbon cleaning =) well hope you figure out your problem...

Sent from my SM-N900V using Tapatalk

[A4BGP]

Get a cheap USB flex shaft inspection camera ( I got a General Tool unit for 39.99 on special) and put it down the plug hole on #3. See if the bore is messed up first. Carbon build up isn't instantaneous...

[LOWFORM]

I'm really surprised your dealer won't 'goodwill' this repair. My service advisor covered my water pump that went out a few months after my warranty expired.

[Fburg A4]

It would be a tough pill to swallow if you pay that muich for a carbon cleaning and it does not remedy a dead miss on cylinder 3. I'm betting the tech saw that the intake was dirty when swapping injectors and it probably does indeed need a cleaning, but it may not solve a dead miss (or it may, who knows). Unless you could get the dealer to tell you ahead of time (or in writing) that if the cleaning does not solve a dead miss they will work with you on the cost of actually fixing the problem, it is a risk without checking plugs, compession, injector balance, etc.

[Ebbsnflows]

I'm really surprised your dealer won't 'goodwill' this repair. My service advisor covered my water pump that went out a few months after my warranty expired.

We are going to attempt to pursue the matter with Audi of America. I'm less than pleased with the dealer's unwillingness to Good-Will it as well. In my opinion, tearing into an engine with only 21K miles, that has had EVERY SINGLE scheduled service performed on time, at the dealership, is absolutely unacceptable. When the service manager and I were going back and forth about the cost of the service and who should be obligated to pay for it, he stated, "At some point the vehicle's owner has to take some responsibility" I almost lost my sh!t when he said that. I'm sorry...but if the Germans can't engineer an engine that lasts more than 21K miles without a tear down...then they have no business manufacturing cars. He continually went to the well regarding the low mileage being to blame, essentially blaming us for the issue because we don't drive the car that often. I'm sorry...WTF??? We have 4 vehicles....my SS gets driven even LESS (it has 6k miles on it and it's also a 2010). I drive it 2-3 times a month and it fires up every single time, but according to this service manager, with it being 4 yrs old, it'll probably need a tear down/rebuild soon. My 2004 Z06 has 32K miles on it and all of the cylinders fire every time I drive it. But I should probably sell it, it must be living on borrowed time using an Audi's lifespan to measure. My 2007 4Runner has a ridiculously high 44k miles on it...Geez, I was going to take it to the beach next week...I don't know now, according the Service rep, 21K mile motors are ticking time bombs so the 4runner may blow up any freakin' day.

Pardon the sarcasm...but I don't care how you spin it, meticulously maintained 21k mile motors in $50k cars shouldn't need to be cracked up open for repairs. And if they are...the manufacturers need to step up, own the issue and fix it.

[A4BGP]

Right, perhaps you should inform your Service Advisor that you have considered his "advise" and will, henceforth, drive the car like your -not stock- R1! I imagine THAT should be more inline with his idea of "normal use" ...Fuckin'idiot! Ask him what he does with the cars that sit on his sales lot for months at a time? Do they invariably turn to shit from lack of use and get rebuilt?

[hookahmaster]

I'm really sorry to hear about this. I hope all goes well! I royally hate dealerships they are the biggest scam artists of life. This is why sometimes I wish I had the equipment, knowledge, and time to do most work myself...

[DoItAllGarage]

Pardon the sarcasm...but I don't care how you spin it, meticulously maintained 21k mile motors in $50k cars shouldn't need to be cracked up open for repairs. And if they are...the manufacturers need to step up, own the issue and fix it.

You hit the nail on the head!

I Scanned over your post. MIsfire on cyl # 3 and if they have ruled out spark or fuel problems, next compression check on that cylinder (should be ~180 Psi). If that test comes back bad, then do "leak down test" on that cylinder # 3. During the leak down test if air comes up from the oil dip stick tube... bad news. Piston rings failure :( . I'm in the same boat with you.

[eclipse1]

My car is having the exact same symptom after a stage 2 oil consumption where they replaced pistons and rings. I swapped the spark plug and coil with a different position but issue still on bank 3. Is this related to carbon deposit in the crank case? I didn't ask for a carbon clean out during the engine rebuild. What's the status of your vehicle now?

Sent from my SM-G920P using Audizine mobile app

[richardm0025]

Totally sounds like a leaky injector, I would take it to a different Audi dealership if it's somewhat near you and see what they say. Demand a goodwill repair!


Sent from my iPhone using Tapatalk

[eclipse1]

Totally sounds like a leaky injector, I would take it to a different Audi dealership if it's somewhat near you and see what they say. Demand a goodwill repair!


Sent from my iPhone using Tapatalk

What causes a leaky injector? Would the oil consumption repair have anything to do with this issue?

Sent from my SM-G920P using Audizine mobile app

[richardm0025]

I'm not sure it's somewhat common on B8 models. I had a heavy misfire and had white unburned fuel coming out of the exhaust.


Sent from my iPhone using Tapatalk

[pierreb]

It's so common the injectors are warrantied to 120k miles.

[eclipse1]

Turned out to be a bad coil or a spark plug. Replaced all plugs and a single coil pack and the car is running like before.