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So the highway was empty at 2am the other day. Put the transmission in M mode and did several 40 mph to “censored” mph pulls for fun. Then slowed down, put to the car in D, stopped at the stop light and the car started shaking with a flashing check engine. Scanned it and found P0302 aka missfire in cylinder 2. Went to bed and decided to check again in the morning. The car runs perfect. No issues whatsoever. Changed the spark plug anyway. Also swapped the coil for the one from the cylinder 1. All of the plugs had been changed 10k miles ago using NGK. The car has been running fine. It shaked for 5ish seconds today without any codes then worked fine. Also I noticed sometimes it kinda fires up too fast. When it does so I smell gasoline.
Any ideas? Should I change all the plugs just in case? The car is 2007 E63.
Not sure that means it isn't the injectors. See if you can get it to misbehave at home and when it does, shut it down immediately and examine the plug for #2 (and maybe check others if you get a hunch to do so). If it is soaked with fuel, after you swapped the coil around, it would seem you have a bad injector. Could also swap injectors around...
Keep in mind I'm giving generic advice - I don't have an M156.
Not sure that means it isn't the injectors. See if you can get it to misbehave at home and when it does, shut it down immediately and examine the plug for #2 (and maybe check others if you get a hunch to do so). If it is soaked with fuel, after you swapped the coil around, it would seem you have a bad injector. Could also swap injectors around...
Keep in mind I'm giving generic advice - I don't have an M156.
Thanks! I gotta get to the bottom of the issue and your suggestion makes total sense. I will do so. I will start with changing all the plugs then as a first step.
Thanks! I gotta get to the bottom of the issue and your suggestion makes total sense. I will do so. I will start with changing all the plugs then as a first step.
Any luck with your issue?
I have the same or similar issue.
Would get a very intermediate misfire at idle. Finally got a code (P0352) which pointed to a bad coil in Coil 'B" / cylinder 2.
Changed the coil and also did all of the injectors. Now the intermediate misfires are back and more frequent. And it wont throw a freaking CODE!
Lastly, stupid question, but just want to be 200% sure. Cylinder B, on the m156, is second closest to bumper on passenger side, correct?
Would get a very intermediate misfire at idle. Finally got a code (P0352) which pointed to a bad coil in Coil 'B" / cylinder 2.
Changed the coil and also did all of the injectors. Now the intermediate misfires are back and more frequent. And it wont throw a freaking CODE!
Lastly, stupid question, but just want to be 200% sure. Cylinder B, on the m156, is second closest to bumper on passenger side, correct?
Haven’t had a chance to do anything yet. I will start with changing the plugs and see if it makes any difference. Did you use OEM or OEM quality injectors and coils as a replacement?
I had ignition coil issues for a good year before they failed. I would see random bursts of misfires once every 1-4 months so I shrugged it off...when they did fail one did then 3 others on the same day. barely got home as luckily I was 2 miles away.
replaced with new coils and has been great ever since.
I had ignition coil issues for a good year before they failed. I would see random bursts of misfires once every 1-4 months so I shrugged it off...when they did fail one did then 3 others on the same day. barely got home as luckily I was 2 miles away.
replaced with new coils and has been great ever since.
I didn’t even know that there were different codes for the coils and plugs. If the plugs don’t make any difference then coils are next on the list. What brand did you get? Fcp sells Delphis but I don’t know whether they are good or not.
Went with FCP Delphi's. Delphi is an OEM supplier, not sure if for Mercedes AMG but OEM supplier for sure. If you've replaced injectors, coils, plugs all that's left is air leak or coolant leak.
Delphi has a long and pretty good history as an automotive supplier. One of their many claims to fame was the development (with GM, actually GM owned them at the time and for a long time) of the famous magnetorheological shock system. Where I come from, Delphi is a good name.
Haven’t had a chance to do anything yet. I will start with changing the plugs and see if it makes any difference. Did you use OEM or OEM quality injectors and coils as a replacement?
Yes, all OEM stuff. I forgot to mention I also just replaced the plugs.
Originally Posted by hachiroku
I had ignition coil issues for a good year before they failed. I would see random bursts of misfires once every 1-4 months so I shrugged it off...when they did fail one did then 3 others on the same day. barely got home as luckily I was 2 miles away.
replaced with new coils and has been great ever since.
wow, that’s crazy. The random burst is exactly what I am experiencing. It won’t happen for along time but when it does, it’s like 5-6 times. Then stops.
when you say one failed, how did you know? Did you get a code? Around what mileage?
that’s wild more failed after you changed the first. Did you end up doing all 8? Or just 4?
A good aftermarket scan tool can check for rough running cylinders without needing a code. I didn't see a misfire count (on individual cylinders) like GM which would have been really handy.
I swapped the coil from cylinder 2 with the one from the cylinder 1. I also dropped a brand new plug in cylinder 2. I am still experiencing random misfire on cylinder 2.
This issue always happens after driving the car and then letting it sit for 20 minutes or so, and then starting again. It has never happened when starting it cold in the morning. There is always a tapping sound at the start-up when it happens. Imagine if you tapped on the valve cover with a screwdriver— that kind of sound followed by misfires and shaking. Turning the car off and then back on helps sometimes.
Some say it could be a cracked valve spring. I am scared -
Based on the symptoms it could very well be injectors start leaking occasional. Common issue for this motor when it get some millage on it's back
Been though the same problem with my 2008 E63 about a year ago 130K millage on the clock at that time. Had similar symptoms as you described on the way to the airport one day. At that time I suspected there were misfire at least on a couple of cylinders. Came back a week later started it up. No problems however after one minute of idling symptoms was back. Left the car in the airport as I had another trip following day.
Came back to the airport next day put a scan tool on confirming misfire on several cylinders. A week later back again in the airport started up again same problem. Also noticed a heavy greyish smoke coming out of the exhaust while misfiring and a faint smell of gasoline
Had it picked up and brought to an Authorized MB dealer. They use a whole day to troubleshoot and called at the end of the day they had not did not find the problem and has not been able to replicate the issue but saw there were cross termination going on in the motor and wanted to pull of the heads.
No way..... At that time I pulled the plug as I did not believe their explanation and asked the dealer to stop any work. I knew Top header bolts were fine and there was no cross termination. I nurse my car :-) and I fixed the Top header bolt issue myself 60K millage ago. I did a complete engine rebuild (bent piston road) at home in my garage as a result of the header bolt issue.
Picked up the car from the dealer. Didn't pay a dime. Drove home (50 mile) with no issue. Scan tool on, found Miss fire fault codes. A that time I suspected injectors!
I did following to check and verify
1) Sparkplug check. Pulled the spark plugs to check for any difference in color and if any were wet or much cleaner that the others. There were a significant difference on a couple. A Leaking injector will clean and slowly remove any old carbon build up over time and two sparkplugs has a difference smell to them
2) Smell test :-) , thin rubber tube inserted through spark plug into the the cylinder. Nose to the tube and inhale:-) You will have no doubt if you have a leaking injector. It's like inhaling gasoline... :-) 2 of my cylinders had a very strong odor of gasoline whereof the 6 others kind of smelled like you would suspect.
3) Borescope check. Used a cheap borescope I had (can be bough on internet for les 20$). Inspected pistons heads though sparkplug hole. Found two that was wet and clean. Most old carbon has bee dissolved and cleaned out. The other 6 were black and dry looking as expected. See below images.
This confirmed by suspicions.
Order a new set of Injectors over the e-Bay. Recommend to replaced all at same time. Cleared fault codes. Started up the engine, Replaced engine oil and filter following just in case any fuel should have contaminated the motor oil.
Problem solved. Now 20K later & 150K on the clock there has not been any miss fire since.
Hope this can can help other in similar cases :-)
Wet and carbon buildup is almost removed by all the gasoline occasional leaking from injector. This cylinder did also smell very strong of gasoline in test 2) This one was even more clean, indicating the injector for this cylinder has been leaking more and/or for a longer time than the other. This cylinder did also smell very strong of gasoline in test 2) As I would expect . Black and dry looking from old carbon build up. No leaking injector. This cylinder and the remaining 5 did not smell of gasoline in test 2)
Thanks for suggestions. I replaced my injectors with Bosch ones recently. I will check for smell; maybe one of them is defective. Don’t recall if the issue was happening before the injector replacement or started after.
wouldn't think they're the issue then. any possibility of you pulling the plugs and taking a photo of each? that may help us diagnose, but a leak down may let us know if its a sealing issue. might as well do a compression test at the same time.
Wet and carbon buildup is almost removed by all the gasoline occasional leaking from injector. This cylinder did also smell very strong of gasoline in test 2)
are you on a factory tune? i see quite a bit of detonation scarring on your pistons. could be caused by that faulty injector as well.
wouldn't think they're the issue then. any possibility of you pulling the plugs and taking a photo of each? that may help us diagnose, but a leak down may let us know if its a sealing issue. might as well do a compression test at the same time.
Thanks man. Thinking about pulling out the injector on cylinder 2 and putting one of the old ones back in to test for faulty injector. The plug on that cylinder is a week old so it will look newer than the rest in any case. Hopefully it is not a faulty lifter. When I did my head bolts all the lifters and cams looked great with a very minor scratches on some of the cam lobes.
are you on a factory tune? i see quite a bit of detonation scarring on your pistons. could be caused by that faulty injector as well.
Almost stock.... Modified Air filter box similar to the European & KN filter, Cylinder heads were resurfaced (not straight) and ported during an engine rebuild. 60 K ago. It popped a cylinder head bolt which also bent a piston rod. Had no other choice than rip the engine out in my garage and rebuild it :-) Comp ratio would have been increased slightly due to the cylinder heads were resurfaced.
Since then I have had occasional detonation noise under certain low load driving conditions and in connection with gas from specific gas stations. I have learned to avoid those and it appears that do the trick. At least I can't hear it anymore.
Update: I took the fuel rail off to investigate the injectors. I saw that the clip holding the cylinder 2 injector wasn't aligned properly. It also seemed to me as the injector slid in place too easily comparing to the rest. I thought maybe the o-shaped gasket was defective. I swapped the gasket on the top of the injector with the one from the old injector, and assembled everything back in place making sure the clip was aligned properly this time. The car has been running great since then.
I don't know how much difference that clip and gasket would make, but apparently, it does.
09-20-2020, 11:13 PM
