Help with check engine code
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Member
Joined: Dec 2009
Posts: 115
Likes: 13
From: Maryland
S550 4-matic
Help with check engine code
Was driving my 14’ cls550 in traffic in ECO mode and out blue it started running real rough had a bad idle and had power but was missing when press on gas. Engine light came on I pulled over listen still had bad idle. Shut car off and back on, no engine light and car ran fine rest way home. Pulled coded and got P0351 if I remember bad ignition A. After looking online believe it’s bad ignition coil on A cylinder. Would appreciate any confirmation or secondary thoughts.
Super Member
Joined: Jan 2017
Posts: 744
Likes: 144
From: Bay Area
W218 Stage 2, E85
I'm not aware of the code, but googling it, it points towards the ignition coils.
Have you performed any service near the coils area lately or change or plugs?
I'll tell you my similar story.
My car, all of a sudden, started shaking/jerking while driving. No CEL. I turned the car off for a few minutes and start it back up. Shaking was gone, still no CEL. this went on for a while. First, I replaced the plugs since I had a ECU tune so just wanted things to be fully functional and not hanging on the last thread of it before it gets worse. The shaking lessened but was still there. So then what I did was I swapped all coils from Bank 1 to Bank 2 and vise versa. Once I did that, the shaking completely went away. Also, I never got a CEL regarding the Ignition Coil. I'm not even sure what was wrong or if any coil was bad or not? I checked all the wirings were connected in a good manner and nothing was lose.
Does the code mentions which bank is it? If it does, I would suggest swap the coils from one bank to the other side, One by One, and check the CEL again if the new code shows if the issue went from Bank1 to Bank 2 or vise versa. If it does, you will know which coil is bad. If you have changed every single coil one by one and kept checking and clearing the CEL after each coil. then you can have a shop use one of the tools, I'm posting the link to the one the shop I went to used to check the functionality of my coils.
https://www.walmart.com/ip/Auto-Coil...881047&veh=sem
He said all coils are fully functional. **This was before I swapped my coils from Bank A to Bank B.
The shop shouldn't charge you for this test as it merely takes less than 3 minutes if you remove the air intake filter housing yourself.
You issue might be completely different, but sounds similar to what I experienced. Though I never had a CEL code for Ignition coil.
Have you performed any service near the coils area lately or change or plugs?
I'll tell you my similar story.
My car, all of a sudden, started shaking/jerking while driving. No CEL. I turned the car off for a few minutes and start it back up. Shaking was gone, still no CEL. this went on for a while. First, I replaced the plugs since I had a ECU tune so just wanted things to be fully functional and not hanging on the last thread of it before it gets worse. The shaking lessened but was still there. So then what I did was I swapped all coils from Bank 1 to Bank 2 and vise versa. Once I did that, the shaking completely went away. Also, I never got a CEL regarding the Ignition Coil. I'm not even sure what was wrong or if any coil was bad or not? I checked all the wirings were connected in a good manner and nothing was lose.
Does the code mentions which bank is it? If it does, I would suggest swap the coils from one bank to the other side, One by One, and check the CEL again if the new code shows if the issue went from Bank1 to Bank 2 or vise versa. If it does, you will know which coil is bad. If you have changed every single coil one by one and kept checking and clearing the CEL after each coil. then you can have a shop use one of the tools, I'm posting the link to the one the shop I went to used to check the functionality of my coils.
https://www.walmart.com/ip/Auto-Coil...881047&veh=sem
He said all coils are fully functional. **This was before I swapped my coils from Bank A to Bank B.
The shop shouldn't charge you for this test as it merely takes less than 3 minutes if you remove the air intake filter housing yourself.
You issue might be completely different, but sounds similar to what I experienced. Though I never had a CEL code for Ignition coil.
