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Another misfire thread, P0300 & P0302

chapusin1

Go Kart Champion
Hey guys,

I'm searching for solutions to my problem, I've searched a few threads but some of them only have the issue when accelerating at mid-rpms, mine only happens at low-rpms and mainly when the car is cold.

I am having errors P0300 and P0302. The dealer told me I need to clean my injectors and valves and offered me a package for ~$200 dlls. I told him, what about the coils? he said if it was the coils the car wouldn't run properly. They also said they checked the spark plugs and they were fine.

My check engine only comes on in the mornings when the car is cold but the dealer tested it when it was warm a few minutes ago and 2 malfunctions were detected. Basically at cold startup it shakes a lot and it hesitates to go, when it's warm it acts perfectly normal, except at stop lights when you can kind of 'feel' the misfires or something going on in the engine.

Error P300 is random/multiply cylinder misfire detected and P302 is cylinder 2 misfire detected.

Here's a video:

http://www.youtube.com/watch?v=97EE3schD5Q

My car is 57k miles, so I could still be covered by the 60k powertrain warranty but since they just replaced an intake manifold sensor under warranty (error p2015) and I'm Stage 2, I don't want to push it.. if it's something I can replace I will do it by myself.

Thanks for your help!

Updates (issue not fixed yet):

Car is 58k miles now
Replaced coils with r8 coils
Replaced spark plugs with NGK Platinum's
Misfires detected on cilnders 1,2,3.
 
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vwgti2.0t

Go Kart Champion
Switch coil packs 2&4 and see if the code follows. Normally I would think cleaning the valves would have nothing to do with it, but HS Tuning just posted a picture to Facebook about massive build up on a car with ~55000 miles. They said it was constantly misfiring on cylinder 3. It looked pretty nasty.

But..definitly try moving the coils around first before you go having the valves cleaned.
 

chapusin1

Go Kart Champion
I will definitely try that, I will get an odb reader to see if the code changes from p0302 to p0304, I just hope it's not a bad injector because then we're talking about a 1k repair
 

chapusin1

Go Kart Champion
I will be updating this thread in case future owners have the same symptoms:

Update: I forgot the dealer cleared the code so I will need to wait until tomorrow morning when the car is cold to get another steady CEL and run it through an ODBII reader to see if I have a faulty coil. Right now the service engine light just blinks but doesn't stay on.

I went to lunch and did a couple of engine redlines, the car feels great when it's not cold. According to the dealer, when the car is cold there's carbon deposits and the cylinder doesn't go all the way down, that's why we get misfires.

More info to come tomorrow.
 

allset

Go Kart Champion
VAG Error Code: 16684

EOBD II Error Code: P0300


Fault Location:
Random/multiple cylinder(s) - misfire detected


Possible Cause:
Spark plug(s).
HT lead(s).
Injector(s).
Ignition coil(s).
Low compression.
Wiring.


VAG Error Code: 16686

EOBD II Error Code: P0302


Fault Location:
Cylinder 2 - misfire detected


Possible Cause:
Spark plug.
HT lead(s).
Injector.
Ignition coil.
Low compression.
Wiring.
 

chapusin1

Go Kart Champion
u stock?

the valve cleaning the dealer does is useless for carbon cleaning, they put solvent in the oil, gas and spray into the TB.

they did that to mine at 35,000 miles. below is my 2010 with 58,000 miles before and after a real carbon cleaning:

http://www.golfmk6.com/forums/showthread.php?t=53613
Just saw your thread.. wow! So the dealer cleanup will be basically useless and also that's something I could do myself. I will research that BG44K or seaform process.

If they did that to yours at 35k, I can't imagine how mine will be at 57k! Mine is stage 2 by the way.
 

allset

Go Kart Champion
Just saw your thread.. wow! So the dealer cleanup will be basically useless and also that's something I could do myself. I will research that BG44K or seaform process.

If they did that to yours at 35k, I can't imagine how mine will be at 57k! Mine is stage 2 by the way.
3M sells the same 3 step kit, with a spray nozzle that hooks over the throttle plar and is long enough so u can sit in the seat and spray while raining the rpms.

but its useless on even moderate build up
 

chapusin1

Go Kart Champion
Update: Switched ignition coils yesterday (2 to 4 and viceversa), issue is still happening. Even detected one more cylinder misfiring, now #1 is doing it as well. Cleared the codes, turned on the car and drove it a for while, I receive no check engine light when it's warm but as soon as I connected the code reader, 300 and 302 codes came up again, even without a check engine light on the dash.

I ordered new spark plugs yesterday, but the car runs great at mid and high rpms, so I'm guessing if it was the spark plugs performance would be degraded wouldn't it?

Thanks for the links, but I don't believe I'll go that route, if it is carbon build up, I will get a full valve cleaning service. I will be using them for preventive maintenance though.

Here's what I found when I took the coil out, some sort of gunk in there I don't know why






Edit: found on another forum that the gunk is actually electrical grease
 
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chapusin1

Go Kart Champion
I'm running out of options here and I'm getting desperate, I ordered R8 Coils and new iridium spark plugs, as grambles mentioned in another thread this fixed his problem. It didn't for me.

Took it to pure motorsports this morning and they said it's unlikely that carbon buildup is causing this, as the car is only 58k miles. Made an appointment for Monday.

I was thinking of seafoaming the valves, but I've also read that if it's really carbon buildup, it won't help at all.

It's very unlikely that 3 injectors went bad and I'm not getting smoke when accelerating, so that's not it either.

What else can I do?
 

allset

Go Kart Champion
I'm running out of options here and I'm getting desperate, I ordered R8 Coils and new iridium spark plugs, as grambles mentioned in another thread this fixed his problem. It didn't for me.

Took it to pure motorsports this morning and they said it's unlikely that carbon buildup is causing this, as the car is only 58k miles. Made an appointment for Monday.

I was thinking of seafoaming the valves, but I've also read that if it's really carbon buildup, it won't help at all.

It's very unlikely that 3 injectors went bad and I'm not getting smoke when accelerating, so that's not it either.

What else can I do?
IDK, are u ko4? i get crazy misfires in neutral and occasional under load. Hyde just went ko4 and has same issue.

are u APR ko4? i may not be for much longer (tune-wise) if i confirm this not to be hardawe
 

chapusin1

Go Kart Champion
IDK, are u ko4? i get crazy misfires in neutral and occasional under load. Hyde just went ko4 and has same issue.

are u APR ko4? i may not be for much longer (tune-wise) if i confirm this not to be hardawe
Nope, I'm stage 2, catted and resonated UR downpipe, Carbonio Intake.

Rought starts got noticeable worse after my downpipe was installed. Also, it's catted and resonated but for some reason it's way louder than the 42dd catted and resonated, maybe there's something wrong with my dp? Don't know if a leak can cause these issues.
 

allset

Go Kart Champion
Nope, I'm stage 2, catted and resonated UR downpipe, Carbonio Intake.

Rought starts got noticeable worse after my downpipe was installed. Also, it's catted and resonated but for some reason it's way louder than the 42dd catted and resonated, maybe there's something wrong with my dp? Don't know if a leak can cause these issues.
i also have catted/res'd UR DP . ive supected a bad/clogged/ core push through cat issue. all which could cause misfires and off sounding exhaust notes.

going to scope it this weekend.
 

chapusin1

Go Kart Champion
What intrigues me is that the car doesn't hessitate all the way to redline, it pulls hard! it's only when it's cold and all the way to warm up, once it's at operating temperature it's totally fine, though at stop lights I feels like something is exploding in the engine in a let's say, asynchronous manner, not uniform, here and there the car shakes a bit.
 

allset

Go Kart Champion
my preference

1 sunoco
2 shell
3 exxon/mobil

all 93 is not equal in octane. BP 93 has been know to cause misfires due to the way they calulate RON
 

chapusin1

Go Kart Champion
i also have catted/res'd UR DP . ive supected a bad/clogged/ core push through cat issue. all which could cause misfires and off sounding exhaust notes.

going to scope it this weekend.
I might take the DP out this weekend, see how it behaves with the stock one.
 
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