[Ampera10]

Sorry for long post
Last winter I start My12 Ampera at -20C, start directly on gas and the engine start to shake and engine light turns on. After about 1 minute, everything fine and until, never had that issue until this year. On last year inspection dealer service told me that error could be a head cylinder as I understand but ignored it, clear the fault and see in future if it's happen again.
Few days ago I start noticing engine runs a little bit shaky(temps are about 4 to 6 celsius), yesterday more than other days so engine light first blinked few times than steady orange. I read wih OBD and Torque app and the error code was " P0300 - Random/Multiple Cylinder misfire detected". I restart the car later, everything normal, put in MM to run on high RPM but nothing out of normal. Later even the engine light turns off. As I talk with other Ampera owners, I blame it on bad fuel and today I fully charged the tank. When I switched to gas, after 1 minute same, start shaking but not that hard like day before and engine light only blink few times. Drive about 10km everything back to normat, tested on high RPM...Later today another 8km drive, after 500m start same problem for 5 sec, engine light back to Orange then all the way back to normal.
I suspect the spark plugs but I have 80k km, I understand that after 100k miles it's time to change them.
P.S - I drive 90% electric.
Someone with same code and how did you fix it?

 

[Total_Idiot]

DTC P0300-P0304
Diagnostic Instructions
• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptors
DTC P0300: Engine Misfire Detected
DTC P0301: Cylinder 1 Misfire Detected
DTC P0302: Cylinder 2 Misfire Detected
DTC P0303: Cylinder 3 Misfire Detected
DTC P0304: Cylinder 4 Misfire Detected


From the repair manual ^^^ the 300 is a general misfire code. Great..this code leads down a rabbit hole of various things to check.
Too many to post.

Your "shaking" might be consistent with a cylinder or more not firing. This could be directly related to fowled plug(s) which might lead to a root cause of oil getting past piston ring(s). Maybe.

Pull plugs and examine is my first suggestion in the hunt for the rabbit.

 

[freshcut]

The thing that comes to mind when I hear this issue is a memory of a BMW my parents used to have. Took it on a trip to Colorado in the late fall one year. No issues at all until after a particularly cold night parked outside (about 20f, so not quite as cold as 20c). Following morning the engine had an obvious misfire. Misfired continuously until we turned it off a couple minutes later. Restarted and ran fine until the following morning, again quite cold and same symptoms, ran a couple minutes and upon starting again, no misfire. Got it into the dealership and they diagnosed that one of the injectors would fail if it was cold, but resumed working fine after it warmed up. This was back in 2007, so I don't recall the details as far as what codes were pulled, but they did eventually recreate the problem after leaving it sitting outside overnight, and that's when they were able to identify the injector itself. I recall initially they thought it was a coil or other ignition system component.

 

[Ampera10]

Thank's for the advice, I just went to the dealer service and change the spark plugs, I attached some images. After changing, the engine was cold and from start I sence the difference and glad to see that engine light turn off after 2'nd ignition. Engine defenetly work different than last days, better I mean. Problem is that after about 5 km, I speed up at maybe 4500rpm to catch a green light and after 100m car start to shake, CEL only blink's few times then I drive about 50 km includes some highway to test it and no problem. So my guess is even I had a very bad fuel, either it's another problem that is combined with spark plugs...I test it again tommorow morning in cold weather like -2 and see if it does it again.
P.S I read some post with someone also change the spark plugs and after few days problem reappear and then working normal again with no problem in the future.

 

[Total_Idiot]

Thank's for the advice, I just went to the dealer service and change the spark plugs, I attached some images. After changing, the engine was cold and from start I sence the difference and glad to see that engine light turn off after 2'nd ignition. Engine defenetly work different than last days, better I mean. Problem is that after about 5 km, I speed up at maybe 4500rpm to catch a green light and after 100m car start to shake, CEL only blink's few times then I drive about 50 km includes some highway to test it and no problem. So my guess is even I had a very bad fuel, either it's another problem that is combined with spark plugs...I test it again tommorow morning in cold weather like -2 and see if it does it again.
P.S I read some post with someone also change the spark plugs and after few days problem reappear and then working normal again with no problem in the future.
View attachment 160115 View attachment 160117

I don't like the look of those plugs. Anyone else? Seems like oil is getting past the piston rings a little bit.

Recommend you pull a plug out after 5K & 10K to inspect. Keep on taking pics ! Or replace plug in one cylinder after 5K, then same cylinder after 10K.

I would suggest checking oil level every 1K mile..

http://ww2.justanswer.com/uploads/hondatech/2012-05-09_170309_honda_oil_consumption_job_aid.pdf

You can perform an oil consumption test too (I would recommend weighing oil v. trying to get precise volume measurements which is harder -- convert to volume via density), above is a test procedure FYI

 

[Ampera10]

The mechanic did't tell me nothing suspecting the oil pass thru cylinder, only that maybe one or two of the plugs were making spark beside is use to, not in the middle and show me a white spot on the spark. Before CEL appears I've done the oil and filter change, maybe a coincidence. I've checkd the oil level, maybe it's above maximum but it's just under max, so it's fine. I never had lost oil.
I just got back from a morning test at -2C and everything is normal, drive few km on highway with no problem. Fuel consumption seems back to normal.
PS, oil on spark supose to be greesy if I've had oil there, this one look like smoked.

 

[Ampera10]

Back with details.
So the problem was not solved 100% by changing the spark plugs but obviosly the car drives way better, but still in 3 weeks only 3 times for few sec I had a CEL blinking / misfire. Still, the temps are now like 10C son not the same like -6c when the problem first started. Today a drive to the dealer service for diagnose and the CEL got back(only blink 3 sec) on way to the service (TODAY WAS RAINING AND AS I REMEMBER EVERYTIME i GOT THE CEL WAS MOISTER OR AFTER RAIN) so I got there, put the car on tester and found only history faults, P0300 random cylinder misfire.
If anybody knows, the guy that inspected the car said it cannot be the coil pack because I got misfire on all cylinder at once and not all the time. So they told me to drive and finish remaining fuel and put from another gas station, maybe it was bad fuel.
Since first time i've got this problem, I put like 25l of fresh fuel on top of exesting one. I don't know if it was the fuel or the spark plugs change but the car runs way better then before. Also the weather is warmer.
Any sugestion is apreciated.
If it's not a bad coil then I'm out of ideas. Is there anu method of testing the coil? I guess the tester is not showing if it is bad or not.

 

[Murrcar]

Have the tech check the fuel pump pressure/flow. Could be starving for fuel at high loads.

 

[DQL]

My 2011 also started misfiring, which was a surprise, since I think the engine has less than 10K miles on it.

I think it was caused by rats sitting on the top of the engine. We live near a creek, and rats will sleep under the hood at night. There is usually some rat droppings on the top of the engine whenever I service it.

Anyway, I think they also pee up there. And the pee runs down into the spark plug area. If any liquid ever gets into the spark plug cups, it will stay in there.

I was able to fix the misfire problem simply by cleaning the entire area thoroughly, pulling the plugs, and cleaning the base with a wire brush. All the plugs had a lot of white residue/oxidation around the porcelain, which might have been the cause of the ignition short.

Probably not exactly your problem, but might be worth just pulling the coil plate and cleaning up the entire area. Vacuum/Blow out the plug hollows before pulling the plugs, to avoid dropping accumulated crud into the engine.